Neilsen Drill Power Extension Bar Socket Adapter Converter Set 1/4″ 3/8″ 1/2″ Sizes: 1/4”Dr x 65mm long, 3/8”Dr x 65mm long, 1/2”Dr x 70mm long. Sandblasted finish. Spring ball bearing fastens sockets securely. Turns any power drill into a power nut driver. 1/4” hex shaft fits all quick-change adaptors & extensions, drill chucks.