S-91781A166 1-72 x 1/4" ASME B18.6.3 Stainless Steel Slotted Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with 18-8 stainless steel construction and passivated finish, ideal for harsh industrial environments
• Superior mechanical strength delivering 80,000 psi tensile strength and Rockwell B80 hardness for reliable, long-lasting fastening
• Precision thread engagement with Class 2A fit and UNF fine threading ensures secure, vibration-resistant connections
• Optimal flush mounting featuring standard 82° countersink angle for seamless surface integration in precision assemblies
• Full-threaded design maximizes grip length and load distribution across the entire 1/4" fastener length
• Regulatory compliance meets ASME B18.6.3 specifications while being RoHS 3 and REACH compliant for global industrial applications
• Simplified installation with slotted drive design providing straightforward manual assembly in confined spaces

Professional Applications & Engineering Value

These 1-72 UNF flat head slotted screws deliver critical engineering advantages in precision-driven applications. The combination of 18-8 stainless steel and passivated finish provides exceptional protection against corrosion and chemical exposure, making them ideal for electronics, instrumentation, and marine equipment where environmental resistance is paramount. The fine UNF threading with Class 2A fit ensures precise, secure fastening in thin materials and delicate assemblies, preventing thread stripping while maintaining consistent clamping force. The 82° countersink angle allows for perfect flush mounting in precision machined components, eliminating protrusions in tight-clearance applications. These fully threaded screws distribute stress evenly across their entire length, reducing point loading and enhancing joint integrity in vibration-prone environments.

Specification Summary & Compliance

Manufactured to exacting ASME B18.6.3 standards, these screws feature precision Class 2A thread fit with 1-72 UNF fine threading and right-hand thread direction. The 82° countersink angle conforms to industry standards for flat head fasteners. Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations ensures environmental safety and unrestricted use in industrial markets worldwide. Mechanical properties include 80,000 psi tensile strength and Rockwell B80 hardness for demanding applications.