Specifications:The structure is heavy-duty heat-treated chromium vanadium steel with superior strength.With highly durable black electrophoretic paint finish, it has corrosion resistance, and can eliminate rust.The spring-loaded stop ball is firmly locked on the socket.Special impact grade design is for drivers and wrenches, and the spring ball bearings on each square head are firmly fixed and locked in the socket to avoid slipping during use.Item Name: Wrench Socket Adapter KitMaterial: Tool SteelQuantity: 9Pcs/SetConversion Rod: 1/2", 3/8", 1/4"Conversion Head: 1/2"-3/8", 3/8"-1/2", 3/8"-1/4", 1/4"-3/8"Features: Anti-rust, Corrosion Resistance, DurableRod Length: 72mm/2.83", 64mm/2.52", 60mm/2.36" (Approx.)Conversion Head Diameter: 10mm/0.39" (Approx.)Notes:Due to the light and screen setting difference, the item& 39;s color may be slightly different from the pictures.Please allow slight dimension difference due to different manual measurement.Package Includes:4 x Conversion Head3 x Conversion Rod2 x Hexagon Socket Rod