S-91249A120 4-40 x 7/8" ASME B18.6.3 Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide coated 18-8 stainless steel, ideal for harsh industrial environments.
• High tensile strength of 70,000 psi ensures reliable, durable fastening under heavy loads and vibrations.
• Rockwell B70 hardness provides excellent wear resistance and long-term performance.
• Coarse UNC threads with Class 2A fit offer quick, easy installation and reduced cross-threading risks.
• Fully threaded design maximizes grip and holding power across the entire 7/8" length.
• Pan head with Phillips No. 1 drive allows for secure, flush mounting and straightforward tool engagement.
• Compliance with ASME B18.6.3, RoHS 3, and REACH guarantees quality, safety, and environmental standards.

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these 4-40 UNC coarse thread screws with black-oxide 18-8 stainless steel construction address common challenges like corrosion, vibration loosening, and assembly efficiency. The rounded pan head and Phillips drive facilitate quick, flush installations in machinery, electronics, and automotive components, reducing installation time and improving aesthetics. With a fully threaded right-hand design and Class 2A thread fit, they ensure consistent clamping force and resistance to shear stresses, making them ideal for applications requiring reliable, repeatable fastening in corrosive or high-stress environments.

Specification Summary & Compliance

This screw features precise Class 2A thread fit per UNC standards, with dimensions including a 7/8" length and 0.112" thread diameter. It complies with ASME B18.6.3 for manufacturing consistency, and meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material reliability.