S-91205A720 1/2"-13 x 2" ASME B18.3, ASTM A574 Alloy Steel Thread-Locking Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional holding power with 170,000 psi tensile strength for demanding industrial applications
• Reliable vibration resistance through integrated nylon patch thread locker that prevents loosening
• Superior corrosion protection from black-oxide coating on alloy steel for extended service life
• Precision thread engagement with Class 3A fit ensuring consistent, secure fastening connections
• Wide temperature tolerance from -70° to 250°F for stable performance in extreme environments
• Optimized drive efficiency with standard hex socket design for high torque application and removal
• Full thread coverage along the 2" length for maximum grip and load distribution

Professional Applications & Engineering Value

Engineered for heavy-duty industrial assemblies, these black-oxide alloy steel socket head cap screws address critical vibration and thermal stability challenges in machinery, automotive, and equipment manufacturing. The nylon patch thread locking feature eliminates the need for separate locking washers or adhesives, reducing assembly time while providing reliable vibration resistance in high-stress environments. With coarse UNC threads and Class 3A thread fit, these fasteners deliver precise engagement and consistent clamping force across the entire 2" length, making them ideal for applications requiring repeated disassembly and reassembly without compromising thread integrity.

Specification Summary & Compliance

Manufactured to ASME B18.3 specifications with Class 3A thread fit precision and UNC 1/2"-13 coarse threads. These socket head cap screws meet ASTM A574 material standards and comply with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. The black-oxide alloy steel construction provides Rockwell C37 hardness and maintains performance across the specified -70° to 250°F temperature range.