S-91251A370 5/16"-24 x 3" ASTM A574 Alloy Steel Socket Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with black-oxide finish, extending service life in harsh industrial environments
• Exceptional tensile strength of 170,000 psi ensures reliable performance under high-stress applications
• Precision Class 3A thread fit provides superior engagement and vibration resistance in critical assemblies
• Partially threaded design offers optimal clamping force control and prevents thread damage during installation
• Fine thread spacing (UNRF) delivers enhanced adjustment precision and superior holding power
• Rockwell C37 hardness maintains structural integrity and prevents deformation under heavy loads
• Standard hex socket drive enables secure tool engagement and efficient installation in confined spaces

Professional Applications & Engineering Value

Engineered for demanding industrial applications, these socket head cap screws combine black-oxide alloy steel construction with Class 3A thread precision to solve critical fastening challenges. The fine UNRF thread form provides superior resistance to vibration loosening in machinery, automotive, and aerospace assemblies where reliability is paramount. The partially threaded configuration ensures precise clamp load distribution while the 170,000 psi tensile strength handles extreme mechanical stresses. Ideal for high-performance equipment requiring consistent fastening integrity, these screws deliver exceptional durability and corrosion resistance through the protective black-oxide surface treatment.

Specification Summary & Compliance

Manufactured to ASTM A574 specifications with Class 3A thread fit precision and UNRF fine thread spacing. Features include 5/16"-24 thread size, 3" length, and 1/4" hex drive. Fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental standards, ensuring safe use in regulated industries.