S-91251A300 3/4"-16 x 3 3/4" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Exceptional tensile strength of 170,000 psi ensures reliable performance under extreme loads, reducing the risk of fastener failure in critical assemblies.
• Superior corrosion resistance from the Black-Oxide finish on alloy steel, extending service life in harsh industrial environments.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant connections in high-precision machinery.
• Fine UNRF threads offer improved load distribution and better sealing capabilities compared to coarse threads.
• High hardness (Rockwell C37) enhances wear resistance, maintaining thread integrity through repeated installations.
• 5/8" hex drive compatibility allows for high-torque installation with standard tools, speeding up assembly processes.
• Partially threaded design with 2" minimum thread length provides optimal grip range for varied material thicknesses.

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these Black-Oxide alloy steel socket head cap screws deliver critical performance where standard fasteners fail. The combination of UNRF fine threads and Class 3A fit creates superior vibration resistance in heavy machinery, automotive assemblies, and precision equipment. The Rockwell C37 hardness ensures dimensional stability under repeated stress cycles, while the 170,000 psi tensile strength provides margin for safety-critical connections. The Black-Oxide surface treatment offers moderate corrosion protection without compromising dimensional accuracy, making these screws ideal for applications requiring both strength and environmental resistance. The 5/8" hex drive accommodates high installation torque values, ensuring reliable clamping force in structural applications.

Specification Summary & Compliance

Manufactured to ASTM A574 specifications with Class 3A thread fit for precision applications. Features UNRF fine threads (3/4"-16) with 2" minimum thread length on a partially threaded shank. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards. Dimensions include 1 1/8" head diameter, 3/4" head height, and 3 3/4" overall length with standard socket head profile.