S-91251A087 1/4"-20 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 high-stress conditions, reducing the risk of fastener failure in demanding applications.
• Superior corrosion resistance from the black-oxide finish prolongs service life in harsh industrial environments, minimizing maintenance and replacement costs.
• Precise Class 3A thread fit provides tighter tolerances for secure, vibration-resistant connections, enhancing assembly integrity.
• Partially threaded design allows for controlled clamping force and easier alignment, ideal for applications requiring specific grip lengths.
• High hardness (Rockwell C37) offers excellent wear resistance, maintaining thread integrity through repeated use and disassembly.
• Coarse UNC threads enable quick installation and reduced cross-threading risks, speeding up assembly processes.
• Hex socket drive with 3/16" size facilitates easy access in confined spaces and provides high torque transmission without slippage.

Professional Applications & Engineering Value

Engineered for high-strength industrial fastening, these black-oxide alloy steel socket head cap screws address critical challenges in machinery, automotive, and heavy equipment sectors. The Class 3A thread fit and coarse UNC threading ensure rapid, secure installations even in high-vibration environments, preventing loosening over time. With a partially threaded rod type, they provide optimal grip where full threading isn't required, reducing material stress. The black-oxide surface treatment combats rust and corrosion, extending component life in humid or abrasive conditions. Ideal for precision assembly applications, these screws deliver consistent performance backed by rigorous manufacturing standards, supporting efficient maintenance and reduced downtime.

Specification Summary & Compliance

This product adheres to Class 3A thread fit for precise dimensional accuracy and UNC coarse thread standards. It meets ASTM A574 specifications for high-strength socket head cap screws, ensuring consistent quality and performance. Compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, it is free from hazardous substances, supporting environmental and safety standards in global supply chains.