S-91263A871 M4 x 20 mm DIN 7991 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with Class 10.9 strength rating and 120,000 psi tensile strength for reliable performance in high-stress applications
• Superior corrosion resistance through zinc-plated alloy steel construction, extending service life in demanding environments
• Optimized installation efficiency with 2.5mm hex drive design providing secure tool engagement and reduced stripping risk
• Enhanced thread engagement through M4 x 0.7mm coarse pitch threading that resists loosening under vibration
• Precise flush mounting with standard 90° flat head profile that sits perfectly countersunk in prepared surfaces
• Consistent dimensional accuracy maintained through Class 6g thread fit tolerance for reliable assembly performance
• Comprehensive regulatory compliance meeting DIN 7991, RoHS 3, and REACH standards for global industrial applications

Professional Applications & Engineering Value

These high-strength metric flat head screws are engineered to address critical fastening challenges in industrial machinery, automotive assemblies, and heavy equipment applications. The zinc-plated alloy steel construction provides essential corrosion protection while maintaining the Rockwell C32 hardness required for repeated disassembly and reassembly cycles. The fully threaded M4 x 0.7mm coarse pitch design ensures maximum thread engagement and superior vibration resistance, preventing loosening in dynamic operating environments. The standard 90° countersink angle and flat head profile facilitate flush mounting in precision applications where protrusion cannot be tolerated. These Class 10.9 fasteners deliver the structural integrity needed for critical joints while the 2.5mm hex drive simplifies installation in confined spaces common in industrial equipment maintenance and manufacturing operations.

Specification Summary & Compliance

This M4 x 0.7mm x 20mm flat head screw features Class 6g thread fit tolerance according to ISO metric standards, ensuring precise dimensional accuracy for reliable assembly. Manufactured to DIN 7991 specifications with full compliance to RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The fastener maintains Class 10.9 mechanical properties with verified 120,000 psi tensile strength and Rockwell C32 hardness, confirming its suitability for high-performance industrial applications requiring certified material traceability and regulatory compliance.