S-91771A969 1/4"-20 x 1/2" ASME B18.6.3 Stainless Steel Phillips Flat Head Screws
Stainless Steel Phillips Flat Head Screws
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Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
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Key Features & Benefits at a Glance
- Superior corrosion resistance from passivated 18-8 stainless steel construction for long-lasting performance in harsh environments
- High tensile strength of 80,000 psi ensures reliable fastening in demanding industrial applications
- Precise Class 2A thread fit provides consistent engagement and reduces cross-threading risks during installation
- 100° countersink angle allows for flush mounting with standard countersunk holes
- Full threading design offers maximum grip length and superior holding power
- Phillips No. 3 drive enables efficient installation with common tools while resisting cam-out
- Compliance with multiple industry standards including ASME B18.6.3, RoHS 3, and REACH for global acceptance
Professional Applications & Engineering Value
These 1/4"-20 UNC flat head screws deliver exceptional engineering value across industrial applications where corrosion resistance and structural integrity are paramount. The passivated 18-8 stainless steel construction provides superior protection against oxidation and chemical exposure, making them ideal for machinery, equipment manufacturing, and outdoor installations. The coarse UNC threading ensures rapid assembly while maintaining secure fastening, and the standard flat head profile with 100° countersink angle creates seamless, flush surfaces that eliminate protrusions in precision assemblies. With 80,000 psi tensile strength and Rockwell B80 hardness, these Phillips machine screws withstand vibration and dynamic loads in demanding environments, providing reliable performance where fastener failure is not an option.
Specification Summary & Compliance
Manufactured to precise dimensional standards with Class 2A thread fit tolerance and UNC coarse threading (1/4"-20). Complies with ASME B18.6.3 specifications for dimensional accuracy and performance. Meets RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) compliance requirements for environmental safety and restricted substances. Features include right-hand thread direction, fully threaded design, and standard flat head profile engineered for industrial applications requiring reliable, high-strength fastening solutions.
