S-90429A218 7/8"-14 x 3" ASTM F835 Alloy Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional load-bearing capacity with 130,000 psi tensile strength for reliable performance in high-stress applications.
• Superior thread engagement and vibration resistance due to the Class 3A thread fit and UNF fine thread spacing.
• Optimized for flush mounting with a standard 82° countersink angle, ensuring a smooth, secure surface finish.
• High torque installation capability provided by the 9/16" hex drive, reducing the risk of stripping during assembly.
• Enhanced durability and wear resistance from the alloy steel construction and Rockwell C37 hardness.
• Reliable partial threading design for precise clamping force control without unnecessary thread engagement.
• Compliance with rigorous industry and environmental standards including ASTM F835, RoHS 3, and REACH for assured quality and safety.

Professional Applications & Engineering Value

This alloy steel flat head screw is engineered to address critical challenges in heavy machinery, structural assemblies, and high-vibration environments. The 7/8"-14 UNF fine thread and Class 3A fit provide superior resistance to loosening under dynamic loads, while the partially threaded shank concentrates clamping force exactly where needed. The 82° countersink and flat head design ensure a flush fit, eliminating protrusions in precision equipment. Made from high-strength alloy steel and compliant with ASTM F835, it delivers reliable performance in construction, manufacturing, and industrial maintenance where failure is not an option.

Specification Summary & Compliance

This screw adheres to inch system dimensions with a Class 3A thread fit for high precision. It meets the ASTM F835 specification for mechanical properties and is manufactured in compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring it is free from hazardous substances and suitable for global industrial use.