This 9-piece mixed drive impact socket extension bar set is designed for professional use with impact guns and high-torque tools. Manufactured from durable chrome vanadium steel, it includes three extension bars of each size: 1/4", 3/8", and 1/2" drives. The set features bars of various lengths (50mm, 100mm, 150mm for 1/4"; 45mm, 75mm, 150mm for 3/8"; and 50mm, 125mm, 250mm for 1/2"). The bars are impact-rated for use with impact wrenches and have a ball bearing to secure sockets, preventing them from falling off. The set comes organized in a plastic tray for convenient storage and transport.