The sturdy chrome vanadium steel construction is designed for use with wrenches and spanners. The socket adapters are made of durable chrome vanadium steel for durability and long life. The surface of each adapter is finished with electroplating and blackening, which ensures corrosion resistance. The adapter body is designed with a spring-loaded ball detent and a small hole to keep your sockets stationary and secure. Get the most out of your sockets with this handy set of adapters and reducers that ensure you always have the right size for the job. There are four socket adapters in different sizes and you can use them for different sockets. Can meet your different needs. Features: This is a set of 4 socket adapters and reducers. The sturdy chrome vanadium steel construction is designed for use with wrenches and spanners. A black oxide finish makes each piece anti-corrosion and very durable. The spring-loaded ball detent keeps your sockets still and secure. Specifications: Material: Chrome Vanadium Steel Surface Finish: Electroplating, Blackening Quantity: 4pcs Color: Black Size: 1/2" (Square Hole) - 3/8" (Square Head) 3/8" (Square Hole) - 1/4" (Square Head) 3/8" (Square Hole) - 1/2" (Square Head) 1/4" (Square Hole) - 3/8" (Square Head) Package Includes: 4 x Socket Reducers