S-91400A118 4-40 x 7/8" FF-S-92, QQ-P-35, MS51957-20 Stainless Steel Pan Head Phillips Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with passivated 18-8 stainless steel construction, ideal for harsh environments and extended service life.
• High tensile strength of 80,000 psi ensures reliable load-bearing capacity and structural integrity in demanding applications.
• Coarse UNC threads with Class 2A fit provide faster installation and secure fastening, reducing assembly time and improving efficiency.
• Fully threaded 7/8" length offers maximum grip range and consistent holding power along the entire shank.
• Phillips drive and rounded pan head enable easy installation with standard tools while providing a low-profile, finished appearance.
• Compliance with Fed. Spec. FF-S-92, QQ-P-35, and MS51957-20 guarantees consistent quality and interchangeability for government and industrial projects.
• RoHS 3 and REACH compliant for environmentally responsible and safe use in regulated markets.

Professional Applications & Engineering Value

Engineered for precision and durability, these 4-40 UNC rounded head screws address critical needs in industrial assembly, electronics, and machinery. The passivated 18-8 stainless steel provides excellent resistance to oxidation and chemical exposure, making them suitable for outdoor, marine, or high-humidity environments. The coarse thread design ensures quick, secure fastening in materials where fine threads might strip, while the Phillips drive allows for efficient torque application with common tools. Fully threaded from head to tip, these screws deliver uniform clamping force, preventing loosening under vibration and enhancing the reliability of panel mounting, enclosures, and structural frameworks. Their compliance with stringent standards ensures they meet the exacting requirements of aerospace, defense, and commercial manufacturing sectors.

Specification Summary & Compliance

This screw features a 4-40 UNC coarse thread with Class 2A tolerance for consistent fit and performance. It is manufactured in accordance with Fed. Spec. FF-S-92, QQ-P-35, and MS51957-20, ensuring adherence to dimensional and material specifications. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, confirming its safety and environmental responsibility for global supply chains.