[Material]Steel High carbon steel, high quality material to avoid during use. [General Use]These extensions, adapters and reducers are designed for Impact use and feature spring-loaded stop balls to lock the sockets securely, while through-holes on the drive end of the adapters and reducersreducers lock onto the drive shaft.convenience, regardless of which tool you choose to use. [High Quality]Extension adapters are made of heat treated chrome vanadium steel with black oxide coating.Adapters and reducers are made from premium, high-strength chrome steel with a manganese phosphate coating to help resist rust and corrosion.a lifetime of use. [Widely Application]Fits 1 or 4" quick change chuck systems or directly into drill chuck.Any cordless electric drill in a nut driver.Convenient for quickly driving nuts, bolts and fasteners etc.Spring loaded ball bearing on head holds sockets securely. Ideal for DIY, household maintenance and most general repairs Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.