S-92805A540 1/4"-20 x 3/4" ASME B18.3, ASTM F879, MIL-DTL-18240 Stainless Steel Thread-Locking Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Permanent vibration resistance with nylon patch locking that maintains integrity from -65° to 250° F, ideal for high-stress environments
• Superior corrosion resistance from 18-8 stainless steel construction, ensuring longevity in harsh industrial settings
• High tensile strength of 70,000 psi and Rockwell B55 hardness for reliable load-bearing in demanding applications
• Secure, precise fastening with Class 3A thread fit and UNC coarse threads, reducing the risk of loosening under vibration
• Easy installation and removal using a standard 5/32" hex drive, compatible with common tools for efficient maintenance
• Flush mounting capability with an 82° countersink angle and standard flat head profile for seamless surface integration
• Full thread engagement along the 3/4" length, providing maximum holding power and stability

Professional Applications & Engineering Value

This 18-8 stainless steel flat head screw with nylon patch locking is engineered to address critical challenges in industrial and automotive sectors, where vibration and dynamic loads can compromise fastener integrity. The UNC coarse thread design and Class 3A thread fit ensure tight, reliable connections that resist loosening, while the hex drive allows for high-torque application without slippage. Its fully threaded 1/4"-20 configuration and 82° countersink enable flush mounting in machinery, enclosures, and structural assemblies, reducing protrusion risks. With a temperature-resistant nylon patch, it delivers consistent performance in environments ranging from -65° to 250° F, making it a go-to solution for vibration-resistant fastening in heavy-duty equipment, transportation systems, and precision instruments.

Specification Summary & Compliance

This fastener adheres to Class 3A thread fit tolerances for precision, with 1/4"-20 UNC coarse threads and full threading along the 3/4" length. It meets ASME B18.3, ASTM F879, and MIL-DTL-18240 specifications, ensuring manufacturing consistency and reliability. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, it is free from hazardous substances, supporting safe and sustainable industrial use.