S-94414A573 1/4"-28 x 5/8" ASME B18.3, ASTM F835 Alloy Steel Torx Flat Head Screws

Key Features & Benefits at a Glance

• Exceptional corrosion resistance with black-oxide coating, ideal for harsh industrial environments
• Superior torque transmission and reduced cam-out with Torx Plus IP30 drive for reliable installation
• High tensile strength (140,000 psi) and Rockwell C39 hardness for demanding structural applications
• Precise Class 3A thread fit ensures secure, vibration-resistant connections in critical assemblies
• 82° countersink angle and flat head design provides a flush, low-profile finish
• Full threading along the 5/8" length maximizes grip and load distribution
• Compliance with ASME B18.3, RoHS 3, and REACH guarantees quality and environmental safety

Professional Applications & Engineering Value

These 1/4"-28 UNF flat head screws are engineered for high-stress applications where reliability is non-negotiable. The black-oxide alloy steel construction offers enhanced durability and resistance to rust, making them suitable for automotive, aerospace, and heavy machinery assemblies. The Torx Plus drive (IP30) minimizes tool slippage, reducing wear on both the fastener and drive bit during high-torque installations. With a fine thread (UNF) and Class 3A fit, these screws provide superior clamping force and vibration resistance in precision equipment. The 82° countersink ensures a seamless fit in tapered holes, preventing surface protrusions and improving aerodynamic or aesthetic profiles in finished products.

Specification Summary & Compliance

This product features a 1/4"-28 UNF fine thread with Class 3A tolerance for precise fit. It is manufactured in accordance with ASME B18.3 specifications (ASTM F835) and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) environmental regulations. Dimensions include a head diameter of 0.531", length of 5/8", and a standard flat head profile with right-hand threading.