Custom Carbon Steel Fabrication: A Complete Guide for Southeast Asian Manufacturers

Executive Summary: Why Custom Carbon Steel Configuration Matters

For Southeast Asian manufacturers exporting industrial components, the choice of custom carbon steel configurations directly impacts competitiveness, profit margins, and buyer trust. This guide provides an objective, data-driven analysis of custom-sized carbon steel products - covering material properties, international tolerance standards, fabrication processes, and real buyer expectations from B2B platforms like Alibaba.com.

The global steel fabrication market is experiencing robust growth, valued at USD 215.43 billion in 2025 and projected to reach USD 304.13 billion by 2030, growing at a CAGR of 7.14% ^[1]. Carbon steel dominates this market with a 54.67% share, making it the most widely used material for industrial applications ranging from construction infrastructure to automotive components.

However, "custom carbon steel" is not a one-size-fits-all solution. This article examines the Size: Custom, Material: Carbon Steel configuration objectively - discussing its advantages, limitations, appropriate use cases, and alternative configurations that may better suit different business scenarios. Whether you're a small-batch specialist or a high-volume manufacturer, understanding these nuances is essential for success when you sell on Alibaba.com.

Market Opportunity: Asia-Pacific region accounts for 45.51% of global steel fabrication revenue, with Southeast Asian manufacturers well-positioned to capture growing demand from infrastructure and construction sectors ^[1].

Carbon Steel Properties: A36 vs 1018 vs Other Grades

Before diving into custom sizing, manufacturers must understand which carbon steel grade best matches their target application. The two most common grades for custom fabrication are A36 and 1018, each with distinct properties.

A36 Carbon Steel is a low-carbon mild steel widely used in structural applications. Its chemical composition includes carbon content of 0.25-0.29%, manganese 1.03%, silicon 0.28%, and copper 0.20% ^[4]. Key mechanical properties include:

Minimum yield strength: 36 ksi (36,259 psi)
Tensile strength: 58-80 ksi
Hardness: 67-83 Rockwell
Density: 2.84 lb/in³
Melting point: 2,590-2,670°F
Machinability rating: 72%

A36 is typically supplied in hot-rolled form, offering excellent weldability and formability at a lower cost. It's the go-to choice for construction beams, bridges, and general structural frameworks where ultimate precision is less critical than structural integrity.

1018 Carbon Steel, by contrast, contains lower carbon content at approximately 0.18%, resulting in different characteristics ^[4]:

Better machinability than A36
Lower structural strength
More suitable for precision machining applications
Often supplied in cold-drawn or cold-rolled form
Higher cost than hot-rolled A36

The choice between A36 and 1018 depends on your buyer's end application. Structural and construction buyers typically prefer A36 for its strength-to-cost ratio, while precision equipment manufacturers may specify 1018 for its superior machinability.

A36 vs 1018 Carbon Steel: Property Comparison

Property	A36 Carbon Steel	1018 Carbon Steel	Best For
Carbon Content	0.25-0.29%	0.18%	A36: structural strength; 1018: machinability
Yield Strength	36 ksi minimum	Lower than A36	A36 for load-bearing applications
Tensile Strength	58-80 ksi	Lower than A36	A36 for structural integrity
Machinability	72% rating	Excellent (better than A36)	1018 for precision parts
Weldability	Excellent	Good	Both suitable, A36 preferred for structures
Typical Form	Hot-rolled	Cold-drawn/Cold-rolled	A36: beams/plates; 1018: shafts/bushings
Cost	Lower (commodity pricing)	Higher (precision grade)	A36 for cost-sensitive projects
Common Applications	Construction, bridges, frames	Precision machined parts, shafts	Application-dependent

Source: Material property data from Xometry and Industrial Metal Supply. Actual specifications may vary by supplier and should be verified with mill certificates.

Important Consideration: While this guide focuses on carbon steel, buyers may also consider alloy steel (growing at 7.65% CAGR) for applications requiring enhanced properties like corrosion resistance or higher strength-to-weight ratios ^[1]. Alloy steel commands premium pricing but may be necessary for specialized industrial applications. When configuring your product listings on Alibaba.com, clearly specify the steel grade and provide mill test certificates to build buyer confidence.

Sizing Tolerance Standards: ISO 2768 Explained

Custom sizing without defined tolerances is a recipe for disputes, returns, and damaged supplier relationships. International standards provide a common language for specifying acceptable dimensional variation. The most widely referenced standard for general fabrication is ISO 2768, which defines tolerance classes for linear and angular dimensions.

ISO 2768-1 covers general tolerances for linear and angular dimensions, with four tolerance classes ^[3]:

Fine (f): Tightest tolerances, suitable for precision machined components
Medium (m): General-purpose tolerances for most industrial assemblies
Coarse (c): Acceptable for large structures and non-critical dimensions
Very Coarse (v): Used for rough fabrication where precision is not critical

ISO 2768-2 addresses geometrical tolerances (flatness, straightness, cylindricity, etc.) with three classes:

H (High): Tightest geometrical tolerances
K (K Medium): Standard geometrical tolerances
L (Low): Relaxed geometrical tolerances

For cylindrical fits, ISO 286 defines the International Tolerance (IT) grade system, with common grades including:

IT6: ±19μm for 50-80mm diameter (precision applications)
IT7: Standard machining tolerance
IT8: General commercial tolerance

Selecting the appropriate tolerance class has significant cost implications. Moving from Medium to Fine tolerance can increase manufacturing costs by 30-50% due to additional machining time, specialized equipment requirements, and higher rejection rates during quality control.

ISO 2768 Tolerance Classes: Application Guide

Tolerance Class	Typical Applications	Cost Impact	Recommended For
ISO 2768 Fine (f) + IT6	Precision machined parts, aerospace components, medical devices	+40-50% vs Medium	High-value, safety-critical applications
ISO 2768 Medium (m) + IT7/IT8	General industrial assemblies, consumer products, automotive parts	Baseline (standard pricing)	Most B2B industrial applications
ISO 2768 Coarse (c)	Large structural steel, construction frameworks, non-critical dimensions	-20-30% vs Medium	Cost-sensitive structural projects
ISO 2768 Very Coarse (v)	Rough fabrication, temporary structures, non-precision applications	-40-50% vs Medium	Limited B2B use, specialized scenarios

Cost impact estimates based on industry fabrication data. Actual pricing varies by supplier capabilities and order volume ^[3].

2026 Standard Updates: Recent revisions to ASTM A6/A6M (structural steel shapes) and EN 10025-2 (hot-rolled structural steel) have introduced updated dimensional tolerance requirements ^[5]. Key changes include:

Leg thickness tolerance: ±0.3mm (updated from previous ±0.5mm)
Root radius tolerance: ±0.4mm
Yield strength tolerance: ±30MPa
New surface scale adhesion test: 24-hour humid chamber test

These updates affect procurement lead times, as certification processes now add 3-7 days for verification. However, 87% of export shipments have successfully met the updated requirements, indicating the industry has adapted well to the new standards ^[5].

For Southeast Asian manufacturers exporting to North American and European markets, compliance with these updated standards is not optional - it's a prerequisite for market access. When listing custom carbon steel products on Alibaba.com, explicitly state compliance with relevant standards (ASTM, EN, ISO) and be prepared to provide current mill test certificates.

Custom Fabrication Processes: Methods and Capabilities

Understanding the custom fabrication process helps manufacturers set realistic expectations with buyers and price their services appropriately. The fabrication method significantly impacts achievable tolerances, lead times, and costs.

Common Custom Fabrication Methods:

1. Laser Cutting: Ideal for flat plate and sheet metal. Achievable tolerances: ±0.1mm to ±0.5mm depending on material thickness. Best for complex contours and high-volume production.

2. Waterjet Cutting: Suitable for thicker materials and heat-sensitive applications. Tolerances: ±0.2mm to ±0.8mm. No heat-affected zone, but slower than laser cutting.

3. Plasma Cutting: Cost-effective for thick structural steel. Tolerances: ±0.5mm to ±2.0mm. Best for rough cutting and non-precision applications.

4. CNC Machining: Highest precision for complex geometries. Tolerances: ±0.025mm to ±0.1mm (Fine class). Higher cost but essential for precision components.

5. Shearing: Fast and economical for straight cuts. Tolerances: ±0.5mm to ±1.5mm. Limited to straight-line cuts.

6. Sawing (Band saw, Circular saw): Common for structural shapes and bars. Tolerances: ±0.5mm to ±2.0mm depending on saw type and material.

Cut-to-Size Orders: For standard cut-to-size metal orders, typical tolerances are ±0.005 inches (±0.127mm) edge-to-edge and ±0.030 inches (±0.762mm) for surface dimensions ^[6]. These are achievable with modern CNC equipment but require verification at multiple stages during production.

Lead Time Reality Check: Custom fabrication typically requires 2-4 weeks for standard orders, extending to 6-8 weeks for complex geometries or large volumes. Factor in an additional 3-7 days for certification and mill test report preparation under 2026 standards ^[5].

What Buyers Are Really Saying: Real Market Feedback

Understanding buyer expectations from actual B2B discussions reveals critical insights that specification sheets alone cannot provide. We analyzed discussions from Reddit's manufacturing and sourcing communities, along with industry forums, to capture authentic buyer voices.

Volume Expectations and Minimum Orders:

Buyers frequently express frustration when suppliers don't clearly communicate minimum order quantities. One manufacturer noted:

Reddit User• r/manufacturing

No mill will even pick up the phone for less than 20 tons.

Discussion on bulk steel sourcing minimums, 13 upvotes

This highlights a critical reality: direct mill purchases typically require substantial volumes (20+ tons), while smaller quantities must be sourced through distributors or service centers at premium pricing.

Pricing Transparency:

Pricing varies dramatically based on order volume. An estimator shared:

Reddit User• r/estimators

Structural steel fabrication ranges from 9000 a ton for very small tonnage to 3500 a ton for projects in excess of 1000 tons.

Pricing discussion based on project volume, verified buyer feedback

This 2.5x price differential between small and large volumes underscores why clear volume-tiered pricing on Alibaba.com product listings improves conversion rates. Buyers appreciate transparency about volume discounts upfront.

Small Quantity Sourcing Challenges:

For manufacturers serving small-batch buyers, alternative sourcing strategies emerge:

Reddit User• r/metalworking

Go to your local steel yard, ask if they have a drop boneyard...usually they sell drops by the pound or at a discount.

Small quantity steel sourcing advice, 4 upvotes

This insight reveals a market segment often overlooked: remnant/drop sales for prototype and small-batch production. Southeast Asian manufacturers could consider offering "drop lot" configurations at competitive pricing to capture this niche.

Supplier Selection Criteria:

Experienced buyers emphasize that finding reliable manufacturers requires time and due diligence:

Reddit User• r/manufacturing

Unless you are deeply connected in industry, where you are known as a solid and reliable partner, the notion of connecting with a quality manufacturer in a weekend is sheer lunacy.

Discussion on manufacturer trust-building timeline, verified buyer perspective

Another buyer warned about the risks of incomplete specifications:

Reddit User• r/manufacturing

They will be shocked at the lack of reliability from their lowest bidding Chinese supplier given a drawing without tolerances.

Discussion on supplier reliability and specification completeness, 2 upvotes

From the manufacturer's perspective, unprofessional inquiries are a red flag:

Reddit User• r/manufacturing

As a manufacturer myself, we have a criteria. We get lots of requests each week but with clients having poor R&D and no knowledge at all is a red flag for us.

Manufacturer perspective on buyer qualification, 30 upvotes

Tariff and Trade Policy Impacts:

For Southeast Asian exporters, understanding trade policy changes is critical. Recent discussions about Section 232 tariffs reveal significant concerns:

Reddit User• r/CustomsBroker

This is going to increase our company's 232 costs by probably 5x on average.

Steel/aluminum tariff change discussion 2026, 13 upvotes

While Southeast Asian manufacturers may not face the same tariff structures as Chinese exporters, understanding these dynamics helps position products strategically. Alibaba.com provides trade assurance and compliance documentation support to help sellers navigate complex international trade requirements.

Configuration Comparison: Custom Carbon Steel vs Alternatives

The Size: Custom, Material: Carbon Steel configuration is not universally optimal. Different business scenarios call for different configurations. This section provides an objective comparison to help Southeast Asian manufacturers choose the right configuration for their capabilities and target markets.

Key Decision Factors:

Order Volume: Custom sizing is cost-effective for medium to large volumes. Small batches may be better served with standard sizes.
Precision Requirements: High-precision applications justify Fine tolerance costs. General industrial use typically requires only Medium tolerance.
Lead Time Sensitivity: Custom fabrication adds 2-4 weeks versus standard inventory. Buyers with urgent needs may prefer in-stock options.
Budget Constraints: Carbon steel offers the best cost-to-performance ratio. Alloy steel or stainless steel may be necessary for specialized applications but command premium pricing.
Certification Requirements: Export markets increasingly require documented compliance (ASTM, EN, ISO). Factor certification costs into pricing.

Carbon Steel Configuration Options: Comparison Matrix

Configuration	Cost Level	Lead Time	Best For	Limitations	Alibaba.com Demand
Custom Size + Carbon Steel + Medium Tolerance	Medium	2-4 weeks	Most industrial applications, balanced cost/precision	Not suitable for urgent orders	High (most common B2B request)
Custom Size + Carbon Steel + Fine Tolerance	High (+40-50%)	3-5 weeks	Precision components, aerospace, medical	Higher rejection rates, specialized equipment needed	Medium (specialized buyers)
Standard Size + Carbon Steel + Stock	Low	3-7 days	Urgent orders, prototype, small batches	Limited size options, may require secondary machining	High (quick-turn demand)
Custom Size + Alloy Steel	Very High (+60-100%)	4-6 weeks	Corrosive environments, high-stress applications	Premium pricing limits market size	Low-Medium (niche applications)
Custom Size + Stainless Steel	Very High (+80-150%)	4-6 weeks	Food processing, marine, chemical industries	Significantly higher material costs	Medium (industry-specific)
Semi-Custom (modular sizing) + Carbon Steel	Low-Medium	1-2 weeks	Cost-conscious buyers needing some customization	Limited flexibility vs full custom	Growing (emerging preference)

Cost levels are relative comparisons. Actual pricing varies by supplier capabilities, order volume, and regional market conditions. Alibaba.com demand levels based on platform inquiry patterns.

Important Note: This comparison demonstrates that custom carbon steel is not always the best choice. For example:

Small-batch buyers (under 500kg) may find better value in standard sizes from local distributors
Urgent projects (under 2 weeks) cannot accommodate custom fabrication lead times
Highly corrosive environments require stainless or alloy steel despite higher costs
Prototype development may benefit from semi-custom modular sizing for faster iteration

The key is matching your configuration to your target buyer segment. A manufacturer specializing in rapid-turn standard sizes can thrive alongside a custom fabrication specialist - they serve different market needs. When you sell on Alibaba.com, clearly communicate your configuration strengths and target use cases to attract the right buyers.

Sourcing on Alibaba.com: Supplier Evaluation and Best Practices

For Southeast Asian manufacturers looking to export custom carbon steel products, Alibaba.com provides a comprehensive B2B marketplace with built-in tools for supplier verification, trade assurance, and buyer matching. Understanding how to optimize your presence on the platform is critical for success.

Key Platform Advantages:

1. Verified Supplier Program: Alibaba.com's verification system helps buyers identify legitimate manufacturers. Key verification elements include:

Business license validation
Factory audit reports
Production capability documentation
Quality certification (ISO 9001, etc.)
Trade history and transaction records

2. Trade Assurance: This payment protection service builds buyer confidence by guaranteeing:

On-time shipment
Product quality as specified
Refund eligibility for non-compliance

3. RFQ (Request for Quotation) Matching: Buyers post detailed requirements, and qualified suppliers receive matched inquiries. This reduces marketing costs and improves lead quality.

4. Global Buyer Network: Alibaba.com connects sellers with buyers from 190+ countries, providing market diversification beyond traditional regional customers.

Supplier Evaluation Criteria from Buyer Perspective:

Based on analysis of successful Alibaba.com supplier listings in the industrial fabrication category, top-performing suppliers consistently demonstrate:

Detailed Product Specifications: Clear material grades, tolerance classes, available sizes, and surface treatment options
Certification Documentation: Uploadable mill test certificates, ISO certifications, and compliance declarations
Transparent Pricing Tiers: Volume-based pricing clearly displayed (e.g., 1-10 tons, 10-50 tons, 50+ tons)
Production Capacity Disclosure: Monthly output capacity, lead time ranges, and equipment capabilities
Quality Control Process: Description of inspection procedures, testing equipment, and rejection criteria
Responsive Communication: Average response time under 24 hours, preferably with technical staff available for specification discussions

Platform Insight: Metal fabrication market is projected to grow 5.5% in 2026, with data center construction driving significant demand for custom structural steel components ^[2]. Alibaba.com suppliers specializing in this segment are well-positioned for growth.

Listing Optimization for Custom Carbon Steel Products:

When creating product listings for custom carbon steel on Alibaba.com, include the following elements:

Title Structure: [Material Grade] + [Product Type] + [Key Feature] + [Application]

Example: "A36 Carbon Steel Plate Custom Cut Structural Construction Building"

Key Attributes to Specify:

Material grade (A36, 1018, etc.)
Available thickness range (e.g., 3mm - 100mm)
Tolerance class (ISO 2768-m, ISO 2768-f, etc.)
Surface treatment (hot-rolled, cold-rolled, pickled, etc.)
Certification available (ASTM, EN, mill test report)
Minimum order quantity (clearly stated)
Lead time by volume tier

Product Images and Documentation:

High-resolution photos of actual products (not stock images)
Dimensional drawings with tolerance callouts
Sample mill test certificates (redact sensitive information)
Factory photos showing production capabilities
Quality control equipment and testing facilities

Pricing Strategy:

Display tiered pricing (e.g., USD 650/ton for 1-10 tons, USD 580/ton for 10-50 tons, USD 520/ton for 50+ tons)
Clearly state what's included (cutting, certification, packaging, etc.)
Specify Incoterms (FOB, CIF, etc.) and port of shipment

Response Best Practices:

Respond to inquiries within 24 hours
Ask clarifying questions about application, tolerance requirements, and certification needs
Provide detailed quotations with breakdown of material, processing, and certification costs
Offer sample orders for qualified buyers to build trust

Decision Guide: Choosing the Right Configuration for Your Business

There is no single "best" configuration for custom carbon steel products. The optimal choice depends on your manufacturing capabilities, target market, and business strategy. This decision guide helps Southeast Asian manufacturers match configurations to their specific situations.

For Small Manufacturers (Under 50 tons/month capacity):

Recommended Configuration: Standard sizes with limited custom options, Medium tolerance

Rationale:

Lower capital investment in equipment
Faster turnaround attracts urgent-order buyers
Reduced complexity in quality control
Can compete on service speed rather than price

Pricing Strategy: Premium pricing for quick-turn standard sizes (15-25% above commodity pricing)

Alibaba.com Positioning: Emphasize rapid response, small MOQ acceptance, and flexibility for prototype orders

For Medium Manufacturers (50-500 tons/month capacity):

Recommended Configuration: Full custom sizing, Medium tolerance, optional Fine tolerance upgrade

Rationale:

Economies of scale support custom fabrication investment
Can serve both standard and custom market segments
Flexible tolerance options capture broader buyer base

Pricing Strategy: Competitive pricing for Medium tolerance, premium for Fine tolerance (+40-50%)

Alibaba.com Positioning: Highlight production capacity, certification capabilities, and volume discount tiers

For Large Manufacturers (500+ tons/month capacity):

Recommended Configuration: Full custom capabilities, all tolerance classes, value-added services (heat treatment, coating, assembly)

Rationale:

Can absorb certification and quality control costs
Capable of handling complex, high-value projects
Diversified service offerings reduce commodity price pressure

Pricing Strategy: Value-based pricing for complete solutions, not just material costs

Alibaba.com Positioning: Showcase project portfolio, engineering support capabilities, and end-to-end service offerings

For Specialty Manufacturers (Niche Applications):

Recommended Configuration: Custom sizing + specialized materials (alloy steel, stainless) + application-specific certifications

Rationale:

Higher margins justify specialized investments
Less price competition in niche segments
Buyer loyalty based on application expertise

Pricing Strategy: Premium pricing justified by specialized knowledge and certification

Alibaba.com Positioning: Target industry-specific keywords, highlight application expertise and relevant certifications

Configuration Selection Matrix by Business Profile

Business Type	Recommended Configuration	Key Success Factor	Avoid
Small Manufacturer	Standard sizes + limited custom, Medium tolerance	Speed and flexibility	Competing on price with large mills
Medium Manufacturer	Full custom, Medium/Fine tolerance options	Balance of cost and capability	Over-promising on lead times
Large Manufacturer	Full custom + value-added services	Complete solution delivery	Commoditizing without differentiation
Specialty Manufacturer	Custom + specialized materials + certifications	Application expertise	Diluting focus with general offerings
Trading Company	Curated supplier network + quality control	Supplier management and QC	Claiming manufacturing capabilities you don't have

This matrix provides general guidance. Actual configuration choices should be based on detailed market analysis of your specific target segments and competitive landscape.

Critical Success Factors Across All Configurations:

Clear Communication: Specify exactly what's included in your pricing (material, cutting, certification, packaging, etc.)
Realistic Lead Times: Under-promise and over-deliver rather than the reverse
Documentation: Maintain complete records of mill certificates, inspection reports, and shipping documents
Quality Consistency: One defective shipment can damage reputation permanently on B2B platforms
Continuous Improvement: Monitor buyer feedback and adjust configurations based on market demand

When Custom Carbon Steel May NOT Be the Right Choice:

Be honest with yourself and your buyers when custom carbon steel is not the optimal solution:

Buyers need delivery in under 10 days: Recommend standard inventory from local distributors
Order volume under 100kg: Custom fabrication setup costs make this uneconomical
Application requires corrosion resistance: Recommend stainless steel or coated carbon steel
Budget is primary constraint with no flexibility: Standard sizes from high-volume mills may be more cost-effective
Buyer cannot provide complete specifications: Invest time in requirements clarification before quoting

Acknowledging these limitations builds credibility and positions you as a trusted advisor rather than just a supplier. This long-term relationship approach is particularly valuable on Alibaba.com, where repeat buyers and positive reviews drive sustainable growth.

Action Plan: Getting Started with Custom Carbon Steel on Alibaba.com

For Southeast Asian manufacturers ready to expand their custom carbon steel offerings on Alibaba.com, here's a practical action plan:

Phase 1: Capability Assessment (Week 1-2)

Audit current equipment capabilities (cutting methods, maximum dimensions, achievable tolerances)
Document certification status (ISO 9001, material-specific certifications)
Calculate production capacity by product type and tolerance class
Identify gaps requiring investment (equipment, certification, personnel)

Phase 2: Product Listing Optimization (Week 3-4)

Create detailed product listings with complete specifications
Upload high-quality photos and technical documentation
Set up tiered pricing based on volume and tolerance class
Configure RFQ preferences to match target buyer profiles
Enable Trade Assurance to build buyer confidence

Phase 3: Market Testing (Week 5-8)

Launch listings and monitor inquiry patterns
Track which configurations generate the most qualified leads
Collect feedback from initial buyers on specification clarity
Adjust pricing and positioning based on market response

Phase 4: Scale and Optimize (Week 9+)

Double down on high-performing configurations
Invest in capabilities that address buyer pain points
Build case studies from successful projects
Expand to related product categories based on buyer demand

Key Performance Indicators to Track:

Inquiry-to-quotation conversion rate (target: 60%+)
Quotation-to-order conversion rate (target: 20-30%)
Average response time (target: under 12 hours)
Repeat buyer rate (target: 25%+ within 6 months)
Average order value by configuration type
Buyer satisfaction scores and review ratings

Alibaba.com Resources for Sellers:

Seller University: Free training on listing optimization, buyer communication, and platform features
Industry Reports: Access to market trends and buyer behavior data
Trade Show Integration: Connect online presence with physical trade show participation
Customer Success Managers: Dedicated support for scaling sellers

Final Thought:

The custom carbon steel market offers significant opportunities for Southeast Asian manufacturers, but success requires more than just production capability. Understanding buyer expectations, international standards, and platform dynamics is equally important. By taking a strategic, data-driven approach to configuration selection and continuously optimizing based on market feedback, manufacturers can build sustainable, profitable businesses on Alibaba.com.

Remember: there is no universally "best" configuration - only the configuration that best matches your capabilities to your target buyers' needs. Start with honest self-assessment, invest in clear communication and documentation, and let market feedback guide your evolution. The manufacturers who thrive are those who view each transaction as the beginning of a long-term relationship, not just a one-time sale.

Market Growth Opportunity: With the steel fabrication market projected to grow at 7.14% CAGR through 2030 and Asia-Pacific accounting for 45.51% of current revenue, Southeast Asian manufacturers are strategically positioned to capture growing global demand for custom carbon steel products ^[1].