UNF 1/2 x 3″ A2 Stainless steel. Hex head shoulder bolt. Sold per 1.

Commonly referred to as a setscrew and longer versions are referred to in the United States as a tap bolt. A standard spanner or ratchet is typically used to fit this product. Used for decades on all types of assembly throughout the world. The hex drive allows a higher torque to be applied.