3-piece hex extension adapter set: chrome vanadium steel, suitable for heavy impact engines.The spring-loaded ball bearing on the head rests the sockets securely. Suitable for quick-change 1/4-inch drill chuck systems or directly into the drill. This set is perfect for your impact driver or drill and allows you to replace your ratchet with a power tool.The 1/4-inch hex shank fits all quick-change chucks as well as standard drill chucks.</p>:: 1/4 inch: 66mm long 3/8 inch: 64mm long 1/2 inch: 72mm long</p>4 Piece Socket Adapter, Converter and Reducer Set: Set of four socket adapters, converters and reducers.Allows you to mix and match drive sizes for your sockets, ratchet handles, extensions and other accessories.3/8" (F) to 1/4" (M).1/2" (F) to 3/8" (M).3/8" (F) to 1/2" (M).1/4" (F) to 3/8" (M).Package Includes: 1 x (1/4" Hex Shank to 1/4" Dr) Socket Adapter 1 x (1/4" Hex Shank to 3/8" Dr) Socket Adapter 1 x (1/4" Dr) Hex Shank to 1/2"-inch socket) socket adapter 4 x socket converter set converter and reducer set