Features: Comprehensive set of impact adaptors for use on all types of impact tools Manufactured from strong steel with a phosphate finish for added corrosion protection Easily change the ratchet size up or down Specifiation: 3/8" (F) x 1/4" (M) = 50BV30 CRV HRC 45-47 1/4" (F) x 3/8" (M) = 50BV30 CRV HRC 45-47 3/8" (F) x 1/2" (M) = 50BV30 CRV HRC 45-47 1/2" (F) x 3/8" (M) = 50BV30 CRV HRC 45-47 1/2" (F) x 3/4" (M) = 40 CR HRC 43-45 3/4" (F) x 1/2" (M) = 40 CR HRC 43-45 3/4" (F) x 1" (M) = 40 CR HRC 43-45 1" (F) x 3/4" (M) = 40 CR HRC 43-453/8" (F) x 1/4" (M) = 50BV30 CRV HRC 45-47 1/4" (F) x 3/8" (M) = 50BV30 CRV HRC 45-47 3/8" (F) x 1/2" (M) = 50BV30 CRV HRC 45-47 1/2" (F) x 3/8" (M) = 50BV30 CRV HRC 45-47 1/2" (F) x 3/4" (M) = 40 CR HRC 43-45 3/4" (F) x 1/2" (M) = 40 CR HRC 43-45 3/4" (F) x 1" (M) = 40 CR HRC 43-45 1" (F) x 3/4" (M) = 40 CR HRC 43-45