【High-quality material】The cordless impact driver bit holder is made of high-quality chrome vanadium steel with particularly high hardness and good abrasion resistance. Polished finish and corrosion resistant to make it more durable. 【Easy to Use】The socket set is easy to install and disassemble, and not easy to fall off when using. The nut socket set is very occlusive, firm and flexible. Each socket has obvious size marking, you can quickly find the socket you need. 【1/4" Hex Shank】This hex socket is suitable for installing in tools hexagonal tools such as air screwdriver, electric screwdriver, air drill, electric drill, gun drill, manual screwdriver and more. 【Size ranges】 7 pieces. Socket adapter (inches): 3/16", 1/4", 9/32", 5/16", 11/32", 3/8", 7/16"; 7 Drive Nuts (Metric): 5mm, 5.5mm, 6mm, 7mm, 8mm, 10mm, 12mm. The various sizes of hex drill bits are enough to meet your daily needs. 【Multi-use】Universal 1/4" hex shanks accommodate quick changes and are securely fixed in chucks