Details
5/16-18 x 3 1/2 Hex Head Cap Screws, Steel Grade 5, Zinc Yellow Plating (Quantity: 450 pcs) - Coarse Thread UNC, Partially Threaded, Length: 3 1/2 inch, Thread Size: 5/16 inch

Hex Cap Screws (also called hex head cap screws, hex bolt, or hex head bolt) Manufactured to ASME B18.2.1 and SAE J429 specifications
Features a thick, hexagonal head with chamfered threads
Washer face under the head to provide ample bearing surface when tightened with a wrench
Made from medium carbon steel. You will notice that it’s hexagon head surface is smooth with no markings
Tensile Strength: 120,000 psi 1/4 thru 1 inch diams, all lengths) - 105,000 psi. (1-1/8 thru 1.5 inch diams, all lengths)
When selecting a nut to be used for a graded hex cap screw, keep in mind that the nut should have the same grade as the bolt/screw. For instance, a Grade 5 Hex Cap Screw should only utilize a Grade 5 hex nut