S-90251A542 1/4"-20 x 1 1/4" ASME B18.3 Set Screws

Key Features & Benefits at a Glance

• Vibration-resistant locking with nylon patch thread locker maintains secure fastening in high-stress environments
• Superior corrosion resistance from 18-8 stainless steel construction ensures long-term reliability in harsh conditions
• Precision Class 3A thread fit provides tighter tolerances for enhanced load distribution and joint integrity
• High-temperature performance with locking functionality maintained from -70°F to 250°F for thermal cycling applications
• Optimized torque transmission through 1/8" hex drive prevents tool slippage and installation damage
• Secure component positioning with cup tip design concentrates clamping force for minimal surface marring
• Industry-standard compliance meets ASME B18.3 specifications for consistent quality and interchangeability

Professional Applications & Engineering Value

This 18-8 stainless steel set screw delivers critical performance advantages for demanding industrial applications where vibration resistance and corrosion protection are paramount. The nylon patch thread locking system effectively prevents loosening under dynamic loads, eliminating the need for secondary locking mechanisms in machinery, automotive, and aerospace assemblies. With Rockwell B80 hardness and UNC coarse threads, this fastener maintains structural integrity while providing excellent engagement in both metallic and composite materials. The headless design with hex drive enables flush mounting in confined spaces while permitting high installation torque. Engineered to withstand extreme temperature fluctuations from -70° to 250°F, this Class 3A threaded set screw ensures reliable performance in thermal cycling environments without compromising locking effectiveness.

Specification Summary & Compliance

Manufactured to ASME B18.3 specifications with Class 3A thread fit for precision applications. Features 1/4"-20 UNC coarse threads with right-hand direction and cup tip configuration. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The nylon patch thread locker maintains functionality across the specified temperature range of -70° to 250°F while the 18-8 stainless steel construction provides consistent Rockwell B80 hardness throughout.