All Impact Sockets and accessories are made from high strength alloy steel. Heat treated for the best combination of strength and impact resistance. Optimum wall thickness for strength and access on fasteners having restrictions. Depth of the Hex openings designed to accommodate full standard fastener head. Chamfered openings for ease in engagement with the drive tool and the fastener. Concentric openings and large clearance holes to meet industrial specifications. Ring-N-Pin arrangement for securing them to the drive. Black oxidized coated for increased protection from rusting.