S-91205A050 2-56 x 1/8" ASME B18.3, ASTM A574 Alloy Steel Thread-Locking Socket Head Screws

Key Features & Benefits at a Glance

• Permanent vibration resistance with nylon patch thread locker, preventing loosening in high-stress applications
• Exceptional tensile strength of 170,000 psi for reliable performance under heavy loads
• Wide temperature tolerance from -70° to 250°F, maintaining locking integrity in extreme environments
• Precise Class 3A thread fit ensuring smooth assembly and superior fastening accuracy
• Corrosion-resistant black-oxide finish on alloy steel for enhanced durability in industrial settings
• Standard hex socket drive allowing for high-torque installation with common tools
• Full threading providing consistent clamping force along the entire screw length

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these 2-56 UNC socket head cap screws with nylon patch thread locking deliver reliable performance where vibration resistance is critical. The black-oxide alloy steel construction combined with Rockwell C37 hardness ensures exceptional wear resistance and longevity in machinery, automotive assemblies, and precision equipment. The coarse thread spacing and Class 3A thread fit facilitate quick installation while maintaining precise alignment, reducing assembly time and improving manufacturing efficiency. These fully threaded screws with hex drive design are ideal for applications requiring high clamp force and permanent fastening solutions in confined spaces.

Specification Summary & Compliance

Manufactured to ASME B18.3 specifications with Class 3A thread fit for precision tolerance. Features UNC coarse threads with 2-56 thread size and right-hand thread direction. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards. Meets ASTM A574 material specifications with 170,000 psi tensile strength and Rockwell C37 hardness ratings.