UNC Hex Head Setscrews ASME B18.2.1 4-40 inch in A2 Stainless Steel
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. Produced to ASME B18.2.1.