S-91381A686 4-40 x 1/2" 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
- Secure non-marring fastening with soft brass tip that prevents surface damage to sensitive components
- Superior corrosion resistance through black-oxide coating on alloy steel for extended service life
- Precise thread engagement with Class 3A thread fit ensuring reliable, vibration-resistant connections
- High-strength performance backed by Rockwell C28 hardness for demanding industrial applications
- Easy installation in confined spaces with headless design and 0.050" hex drive compatibility
- Industry-standard compatibility through UNC coarse threading and 4-40 size for broad applicability
- Environmental compliance assurance meeting RoHS 3 and REACH regulations for global usage
Professional Applications & Engineering Value
This 4-40 UNC set screw delivers exceptional engineering value in precision assembly applications where surface protection and vibration resistance are critical. The black-oxide alloy steel construction provides superior corrosion resistance while maintaining Rockwell C28 hardness for high-strength performance. The innovative soft brass tip prevents damage to shaft surfaces and components during secure fastening, making it ideal for precision machinery, automotive assemblies, and electronic enclosures. The headless design with hex drive allows for flush mounting in space-constrained applications, while the Class 3A thread fit ensures tight tolerances and reliable performance in high-vibration environments. These set screws are engineered to solve common industrial challenges of component damage, corrosion, and loosening under dynamic loads.
Specification Summary & Compliance
This precision fastener features 4-40 UNC coarse threads with Class 3A thread fit for superior dimensional accuracy and engagement. Manufacturing complies with ASME B18.3 specifications ensuring consistent quality and performance. The product meets RoHS 3 (2015/863/EU) compliance and REACH (EC 1907/2006) regulations for environmental safety. With a total length of 1/2" and specialized brass tip configuration, this set screw delivers reliable performance in industrial fastening applications requiring precise torque transmission and surface protection.
