SPAX Decking Screws 5x51mm A2 Stainless Steel for Aluminium Joists are specifically engineered for fixing timber decking boards directly to aluminium substructure profiles — no pre-drilling required in aluminium up to 4mm thick. The 51mm length provides additional penetration depth for thicker boards and hardwood applications.

Key Benefits

• Drill point for aluminium — self-drills through aluminium profiles up to 4mm thick without pre-drilling, saving significant time on site.
• Double thread — solid metal double thread for improved grip in aluminium substructures.
• A2 304 Stainless Steel — corrosion-resistant for outdoor decking applications.
• T-Star Plus Drive (T25) — exclusive to SPAX. Provides a positive, secure bit engagement for better driving torque and reduced cam-out.
• Cylindrical head — very low installation height for a minimal overall deck structure.
• Fixing thread — locks the decking board firmly to the aluminium joist for a long-lasting, squeak-free connection.

Application Guide

• 3mm aluminium substructure: suitable for softwood decking
• 4mm aluminium substructure: suitable for hardwood decking
• Recommended accessories: SPAX Air spacer, SPAX Step Drill 4, SPAX Drill 5.2, SPAX Drive STOP
• Not suitable for timbers with heavily interlocked grain

Specifications

• Length: 51mm
• Diameter: 5mm
• Head Type: Cylindrical Head
• Drive: T-Star Plus T25
• Material: A2 304 Stainless Steel
• Quantity: Box of 100
• SKU: 0557000500513

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