The 49-66-6723 Milwaukee SHOCKWAVE Impact Duty 3/8'' Drive 1/2'' Drive Adapter provides you with tool versatility. These adapters convert drive tools to be used with 1/4'', 3/8'' and 1/2'' drive tools and 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 Milwaukee® SHOCKWAVE Impact Duty™ Socket Adapters meet ASME industry standards.