S-91381A351 1/4"-28 x 1/4" ASME B18.3 Set Screws
Set 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 surface protection with soft brass tip that prevents damage to mating components during installation and use
- Exceptional corrosion resistance through black-oxide coating on alloy steel, extending service life in demanding environments
- Precise thread engagement with Class 3A fit ensuring reliable, vibration-resistant fastening in critical applications
- Optimized drive performance with 1/8" hex drive providing secure tool engagement and reduced stripping risk
- Enhanced durability from Rockwell C28 hardness rating, maintaining structural integrity under repeated use
- Industry-standard compliance meeting ASME B18.3 specifications for dimensional accuracy and performance
- Environmental responsibility with RoHS 3 and REACH compliance for safe use in regulated industries
Professional Applications & Engineering Value
This black-oxide alloy steel set screw with protective brass tip addresses critical engineering challenges in precision assembly applications. The fine UNF threads (1/4"-28) with Class 3A fit provide exceptional holding power in machinery, automotive components, and electronic enclosures where vibration resistance is paramount. The headless hex design allows for flush mounting in confined spaces, while the soft brass tip eliminates marring on shafts, gears, and other precision-machined surfaces. Engineered for industrial set screw applications requiring both mechanical strength and surface preservation, this fastener delivers reliable performance in manufacturing equipment, precision instruments, and motion control systems where repeated adjustments are necessary without compromising component integrity.
Specification Summary & Compliance
This precision set screw features 1/4"-28 UNF fine threads with Class 3A thread fit for superior dimensional accuracy. Manufactured to ASME B18.3 specifications with Rockwell C28 hardness rating. The product is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, ensuring safe use across regulated industries. The right-hand thread direction and 1/8" hex drive provide standardized installation compatibility.
