The MILWAUKEE SHOCKWAVE Impact Duty 1/4" Drive to 3/8" Drive Socket Adapter provides tool versatility and durability in high torque applications. This adapter converts 1/4" drive tools to be used with 3/8" drive impact sockets. Milwaukee engineered these adapters with forged steel for durability in high torque applications. The laser-etched size markings allow for easy size identification. The dual-hole design and ring groove make for easy adapter attachment and removal. All SHOCKWAVE Impact Duty Socket Adapters meet ASME industry standards.