S-90344A133 4-40 x 1" ASTM A574 Socket Head Screws with Flat Washer

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance under high-stress conditions, reducing the risk of fastener failure.
• Superior corrosion resistance from the black-oxide finish on alloy steel, extending service life in demanding industrial environments.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant assemblies in critical applications.
• Integrated flat washer distributes load evenly, preventing surface damage and maintaining joint integrity over time.
• Hex socket drive design allows for high-torque installation with standard 3/32" tools, facilitating efficient assembly and disassembly.
• Partially threaded shank offers optimal grip length for materials where full threading isn't required, enhancing versatility.
• Rockwell C39 hardness ensures excellent wear resistance, maintaining thread integrity through repeated use.

Professional Applications & Engineering Value

Engineered for precision assemblies requiring high-strength fastening solutions, this black-oxide alloy steel socket head cap screw addresses common industrial challenges. The 4-40 UNC coarse thread configuration provides excellent engagement in various materials while resisting vibration loosening. With its 170,000 psi tensile strength and Rockwell C39 hardness, this fastener maintains structural integrity in heavy machinery, automotive components, and precision equipment. The black-oxide surface treatment offers superior corrosion protection without significant dimensional changes, making it ideal for applications where both strength and environmental resistance are critical. The included flat washer further enhances performance by preventing embedding and distributing clamp load effectively.

Specification Summary & Compliance

This socket head cap screw features precise Class 3A thread fit with 4-40 UNC coarse threads in right-hand direction. Manufactured to ASTM A574 specification for high-strength alloy steel socket head cap screws. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards. Dimensions include 1" length with 3/4" minimum thread length, 0.183" head diameter, and 3/32" hex drive size. The accompanying flat washer measures 5/16" OD with 0.032" thickness, manufactured from black-oxide steel.