Input Drive: 1/4" FemaleOutput Drive: 3/8" MaleMaterial: Black Oxide Alloy SteelImpact RatedDesigned To Use With Power Tools, Such As An Impact Driver Or Impact WrenchConverts 1/4" Drive Ratchet Or Breaker Bar To A 3/8" DriveOnce Attached, The Unit Will Now Accept Any 3/8" Drive Socket