S-91309A595 5/16"-18 x 3" ASME B18.2.1, ASTM A307 Low-Strength Steel Hex Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with zinc plating for extended service life in harsh environments
• High-strength performance with 60,000 psi tensile strength for demanding industrial applications
• Excellent durability backed by Rockwell B69 hardness for reliable, long-term fastening
• Easy installation and removal with external hex drive design for efficient assembly
• Reliable thread engagement with Class 2A thread fit ensuring consistent, secure connections
• Full-threaded design providing maximum grip length and holding power
• Compliance with industry standards including ASME B18.2.1 for guaranteed quality and performance

Professional Applications & Engineering Value

These 5/16"-18 UNC hex head screws deliver exceptional engineering value for industrial applications where reliability is paramount. The high-strength steel construction combined with zinc plating provides robust protection against corrosion, making them ideal for outdoor equipment, machinery assembly, and structural applications. The coarse UNC thread design ensures quick installation and superior resistance to vibration loosening, while the external hex drive allows for high torque application with standard tools. These fully threaded screws maintain consistent 60,000 psi tensile strength throughout their 3" length, providing uniform load distribution and preventing joint failure in heavy-duty applications across manufacturing, construction, and maintenance sectors.

Specification Summary & Compliance

This hex head screw features precise Class 2A thread fit with 5/16"-18 UNC coarse threads and right-hand thread direction. Manufactured to ASME B18.2.1 specifications using ASTM A307 grade steel, ensuring dimensional accuracy and mechanical properties. The product is RoHS 3 (2015/863/EU) Compliant and REACH (EC 1907/2006) Compliant, meeting current environmental regulations for industrial use.