S-93310A336 1/4"-20 x 7/8" ASME B18.3, ASTM F879, MIL-DTL-18240 Thread-Locking Stainless Steel Button Head Hex-Drive Screws

Key Features & Benefits at a Glance

• Permanent vibration resistance with nylon patch thread locker that maintains secure fastening from -70° to 250° F, preventing loosening in dynamic environments
• Superior corrosion resistance thanks to 18-8 stainless steel construction, ideal for harsh industrial and outdoor applications
• High-strength performance with 70,000 psi tensile strength and Rockwell B55 hardness for reliable load-bearing capability
• Precise thread engagement with Class 3A UNC coarse threads ensuring consistent, secure mating with nuts and tapped holes
• Easy installation and removal using standard 5/32" hex drive, compatible with common industrial tools
• Low-profile rounded button head design provides a smooth finish while maintaining high clamp force distribution
• Full regulatory compliance meeting ASME, ASTM, and military specifications for quality assurance

Professional Applications & Engineering Value

These nylon patch locking rounded head screws deliver critical vibration resistance in demanding applications where fastener integrity is paramount. The 18-8 stainless steel construction provides excellent corrosion resistance for machinery, marine equipment, and food processing applications where moisture and chemicals are present. The permanent nylon patch thread locker eliminates the need for separate locking washers or adhesives, streamlining assembly while maintaining secure fastening across a wide temperature range (-70° to 250° F). With Class 3A UNC coarse threads and fully threaded design, these screws ensure maximum thread engagement and pull-out strength in both metallic and composite materials. The rounded button head profile with hex drive offers both aesthetic appeal and practical installation advantages in confined spaces.

Specification Summary & Compliance

This 1/4"-20 x 7/8" screw features precision UNC coarse threads with Class 3A fit for consistent mating performance. Manufacturing complies with ASME B18.3, ASTM F879, and MIL-DTL-18240 specifications, ensuring dimensional accuracy and mechanical properties. The product is fully RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting the latest environmental and safety regulations for industrial components.