Drop Forged Carbon Steel. Heat Treated and Chrome Plated. Notches in Sockets Lock onto Ratchets or Extensions. Spring-Loaded Ball Bearings Hold Sockets Securely. Contents: * 1pc-3/8" Dr. (F) x 1/4" Dr. (M) Reducer. *1pc-1/2" Dr. (F) x 3/8" Dr. (M) Reducer. *1pc-3/4" Dr. (F) x 1/2" Dr. (M) Reducer.