S-91870A771 1/4"-20 x 1" ASME B18.3 Tamper-Resistant Torx Steel Flat Head Screws

Key Features & Benefits at a Glance

• Enhanced Security: Tamper-resistant Torx T30 drive prevents unauthorized removal, ideal for public or sensitive equipment.
• Superior Strength: 160,000 psi tensile strength and Rockwell C38 hardness ensure reliable performance under high-stress conditions.
• Corrosion Resistance: Black oxide finish provides durable protection against rust and wear in harsh industrial environments.
• Precise Fit: Class 3A thread fit guarantees tight, secure fastening with minimal risk of loosening or cross-threading.
• Flush Installation: Standard flat head with 82° countersink angle allows for a smooth, unobtrusive surface finish.
• Full Thread Engagement: Fully threaded design maximizes grip and load distribution across the entire length.
• Wide Compatibility: Coarse UNC thread and right-hand direction suit various applications, from machinery to structural assemblies.

Professional Applications & Engineering Value

This alloy steel flat head screw with a tamper-resistant Torx T30 drive is engineered to address critical industrial challenges, such as vandalism and unauthorized access in public infrastructure, machinery, and security enclosures. The black oxide finish enhances corrosion resistance, extending service life in demanding environments like manufacturing plants or outdoor installations. Its fully threaded UNC coarse thread design ensures rapid installation and robust holding power, while the 82° countersink angle facilitates a flush fit, reducing snag risks and improving aesthetics. By combining high tensile strength (160,000 psi) and precise Class 3A thread fit, it minimizes failure risks in high-vibration applications, providing reliable, long-term fastening solutions for engineers and maintenance teams.

Specification Summary & Compliance

This screw adheres to ASME B18.3 standards, ensuring dimensional accuracy and performance reliability. It features a Class 3A thread fit for tight tolerances and a coarse UNC thread (1/4"-20) with right-hand direction. Compliance with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations confirms environmental safety and material integrity, supporting sustainable industrial practices.