S-90729A513 5/16"-18 x 1 1/2" Stainless Steel Hex Drive Flat Head Screws

Key Features & Benefits at a Glance

• Superior corrosion resistance with 316 stainless steel construction and passivated finish, ideal for harsh environments and extended service life.
• High-strength performance offering 70,000 psi tensile strength and Rockwell B70 hardness for reliable load-bearing in demanding applications.
• Precise, secure fastening ensured by Class 3A thread fit and UNC coarse thread profile, reducing the risk of cross-threading and loosening.
• Efficient installation and flush finish with a 100° countersink angle and undercut flat head design, providing a clean, recessed appearance.
• Robust drive engagement via the 5/32" hex drive, enabling high torque application and reducing tool slippage.
• Full-threaded design for maximum grip and holding power along the entire 1-1/2" length, enhancing joint integrity.
• Compliance with environmental regulations including RoHS 3 and REACH, ensuring safety and suitability for global industrial markets.

Professional Applications & Engineering Value

This 316 stainless steel flat head screw is engineered to address critical challenges in corrosive and high-stress environments. Its passivated finish significantly enhances resistance to chemicals, saltwater, and industrial atmospheres, preventing premature failure in marine, chemical processing, and outdoor applications. The Class 3A thread fit and UNC coarse thread provide superior vibration resistance and ease of assembly, reducing installation time and maintenance needs. The undercut flat head with a 100° countersink ensures a flush mount, minimizing protrusion and improving aerodynamic or aesthetic surfaces. With a hex drive for secure torque transmission and full threading for consistent clamping force, this screw delivers reliable performance in machinery, structural assemblies, and equipment subjected to dynamic loads.

Specification Summary & Compliance

This screw adheres to precise dimensional standards, including a Class 3A thread fit for tight tolerances and a UNC (Unified Coarse) thread with a size of 5/16"-18. Key dimensions are a length of 1-1/2", head diameter of 0.656", and drive size of 5/32". It is manufactured from 316 stainless steel with a passivated finish and is fully compliant with RoHS 3 (2015/863/EU) and REACH (EC 1907/2006) regulations, ensuring environmental safety and material integrity.