With 6-in-1 functionality, the common size combination doubles the reach and capacity of your jack system, making your unit extremely versatile for multiple repair needs. SET INCLUDES: This adapter set includes 3 pieces. Reducer and 3 pieces. Adapters: 3/8" (F) to 1/4" Drive (M) reducer, 1/2" Drive (F) to 3/8" Drive (M) reducer, 1/4" Drive (F) to 3/8" Drive (M) adapter, 3/8" Drive (F) to 1/2" Drive (M) adapters. DESIGN GUIDE: The adapter's spring-loaded ball locks securely into the socket. Get the most out of your socket with this handy adapter and reducer set, ensuring you always have the right size for the job. HIGH-QUALITY MATERIALS: These adapters and reducers are made of high-strength, heat-treated chrome vanadium steel and have a corrosion-resistant nickel/chrome finish, suitable for industrial, mechanical, or construction projects. These adapters meet and exceed ANSI/ASME standards.