S-90251A108 4-40 x 1/8" ASME B18.3 Set Screws
Set Screws
Image may differ from product. See technical specification for details.
Basic Information
Head Parameters
Dimensions
Thread Parameters
Tip & Drive Parameters
Material & Strength
Temperature & Environment
- Fast delivery
- Enjoy discounts on bulk purchases
- Secure Payment
- Fast Global Shipping
Key Features & Benefits at a Glance
- Vibration-resistant locking with permanent nylon patch thread locker that maintains secure fastening in dynamic environments
- Superior corrosion resistance from 18-8 stainless steel construction, ideal for harsh industrial conditions
- Precision thread engagement with Class 3A thread fit ensuring reliable, tight-tolerance assemblies
- High-temperature performance with thread locker effective from -70° to 250°F for demanding applications
- Space-saving headless design with hex drive allowing flush mounting in confined spaces
- Enhanced durability with Rockwell B80 hardness providing excellent wear resistance
- Wide compatibility with UNC coarse thread spacing for quick assembly and disassembly
Professional Applications & Engineering Value
This 4-40 UNC set screw delivers exceptional engineering value in precision assembly applications where vibration resistance and space constraints are critical concerns. The 18-8 stainless steel construction provides excellent corrosion resistance for machinery, automotive, and electronic enclosures operating in challenging environments. The permanent nylon patch thread locker eliminates the need for additional locking compounds while maintaining secure fastening through thermal cycles from -70° to 250°F. The headless hex drive design with cup tip ensures maximum contact pressure for secure shaft positioning in pulleys, gears, and collars, while the Class 3A thread fit guarantees precise engagement in high-vibration industrial equipment.
Specification Summary & Compliance
This set screw features precision 4-40 UNC coarse threads with Class 3A thread fit for superior dimensional accuracy. Manufactured to ASME B18.3 specifications with Rockwell B80 hardness rating. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations, ensuring safe use across global industrial markets. The 0.050" hex drive provides reliable torque transmission while the right-hand thread direction follows industry standards for consistent installation.
