S-91858A554 1/4"-20 x 3" ASME B18.6.3 Stainless Steel Slotted Flat Head Screws

Key Features & Benefits at a Glance

• Maximum corrosion resistance with 316 stainless steel construction and passivated finish for extended service life in harsh environments
• Superior mechanical strength with 70,000 psi tensile strength and Rockwell B80 hardness to withstand high-stress applications
• Reliable thread engagement through Class 2A thread fit and 1/4"-20 UNC coarse thread design for secure fastening
• Optimal flush mounting with standard flat head profile and 82° countersink angle for seamless surface integration
• Industry-standard compliance meeting ASME B18.6.3 specifications for consistent quality and performance
• Environmental responsibility with RoHS 3 and REACH compliance for safe use across regulated industries
• Versatile partial threading allowing both secure clamping and adjustment flexibility in assembly applications

Professional Applications & Engineering Value

These 316 stainless steel flat head screws deliver exceptional performance in demanding industrial environments where corrosion resistance and mechanical reliability are critical. The combination of passivated finish and marine-grade 316 stainless steel provides superior protection against chemical exposure, saltwater environments, and industrial contaminants. The 1/4"-20 UNC coarse thread design ensures quick installation and secure fastening in various materials, while the partial threading offers optimal clamping force distribution. Engineered with an 82° countersink angle and slotted drive, these screws provide flush mounting capabilities perfect for machinery, marine equipment, food processing systems, and architectural applications where surface smoothness and hygiene are paramount. The 3" length with substantial thread engagement makes them ideal for medium to heavy-duty fastening requirements across multiple industries.

Specification Summary & Compliance

Manufactured to precise dimensional standards with Class 2A thread fit tolerance ensuring consistent threading performance. These flat head screws comply with ASME B18.6.3 mechanical and dimensional specifications, guaranteeing interchangeability and reliability. Environmental compliance includes RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) standards, confirming restriction of hazardous substances. The UNC coarse thread pattern with 1/4"-20 specification and partial threading (minimum 1-1/2" thread length) provides optimal fastening characteristics for industrial applications requiring both strength and corrosion resistance.