Wera 05042673001 | Zyklop Adaptor | Connection 3/8" to 1/2"781 B 3 8" Connection parts, 781 B C x 1 2 x 36 mm x 3 8" Adaptors, 3 8" Connection part 3 8" square head socket to 1 4" external square head. For manual and machine operated tools (non impact), with ball stop groove to safely lock the socket, knurling at the rear end for manageability during manual use; chrome vanadium, dull chromed. 3 8" to 1 2" connection part With 3 8" square head socket drive 1 2" external square With secure socket fixing Made of