S-91255A077 2-56 x 1/4" ASTM F835 Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide coating on alloy steel, extending service life in demanding environments
• Precise Class 3A thread fit ensures reliable engagement and reduces cross-threading risks during assembly
• High tensile strength (120,000 psi) provides exceptional load-bearing capacity for critical applications
• Hex drive design (0.050") offers secure tool engagement and prevents cam-out under high torque
• Fully threaded 1/4" length maximizes grip range and distribution of clamping force
• Coarse UNC threading (2-56) enables faster installation and better performance in softer materials
• Rounded button head profile combines sleek appearance with reduced snagging in confined spaces

Professional Applications & Engineering Value

Engineered for precision assembly in industrial and electronic applications, these black-oxide alloy steel screws address common challenges like vibration loosening and material fatigue. The Class 3A thread fit and coarse UNC threading provide exceptional dimensional stability, reducing installation time while maintaining joint integrity. With Rockwell C39 hardness and 120,000 psi tensile strength, they withstand high-stress conditions in machinery, automotive subsystems, and telecommunications equipment. The rounded head design and hex drive facilitate access in tight spaces, making them ideal for maintenance-critical applications where reliability and corrosion resistance are paramount.

Specification Summary & Compliance

Manufactured to ASME B18.3 and ASTM F835 specifications with Class 3A thread fit and coarse UNC 2-56 threading. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Right-hand threaded with standard dimensional tolerances for consistent performance across industrial applications.