Shockwave, 3/8" Square To 1/4" Hexagonal Socket Adapter allows impact sockets to be used with impact drivers. The Milwaukee® Impact Duty socket adapters are made from a proprietary steel, heat treated to control hardness and provide durability with up to 50X life. The socket adapter has a heavy-duty construction for fastening capabilities in all impacts, built to withstand frequent use and save the expense of having to buy a separate drill driver. Milwaukee® hex to square socket adapters are engineered for maximum durability and long-lasting use. This impact socket adapter is designed for use with impact drivers and impact sockets.