【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 reducers lock onto the drive shaft. convenience, no matter which tool you choose to use. Ideal for DIY, household maintenance and most general repairs 【High Quality】The extension adapters are made of heat-treated chrome-vanadium steel with a 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 1/4" 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