Our Hex Head Cap Screws Grade 5 Steel Plain 5/16-18 x 3-1/4 are designed for high-strength, dependable fastening in a wide range of applications. Crafted from Grade 5 steel with a plain finish, these screws deliver reliable performance in machinery, automotive, and construction projects.

• Size: 5/16-18 UNC
• Length: 3-1/4 in
• Head: Hex Head Cap Screw
• Material & Finish: Grade 5 Steel, Plain
• Best For: General-purpose fastenings in machinery, automotive, and construction

With a hex drive for easy installation and compatibility with standard nuts and washers, these screws provide strong clamping force and durable performance under vibration. Choose these Grade 5 steel plain hex screws for reliable, reusable fasteners on assemblies that require a clean, uncoated surface.