1. Dimension The length of the metal hose extension rod set is 60mm / 2.36 inch 100mm / 3.94 inch 150mm / 5.91 inch. The size of the hexagonal shank connecting the electric drill is 6.35mm (1/4 inch), and the size of the hexagonal part of the connecting bit is 6.35mm (1/4 inch). 2. Material This extension extend socket drill bit holder is made of high quality chrome vanadium steel which makes it practical and durable. The surface is designed with electroplating, which is not easy to rust. The hexagonal joint has strong magnetism, which is not easy to fall and is easy to disassemble. 3. Convenience Easy to use and install. The product has a small area and is easy to carry and store. It can be carried with you in case of emergency. 4. Compatibility The extension shaft can be connected to a low speed DC hand electric drill, rechargeable power drill or manual wrench, manual screwdriver or electric screwdriver (low speed). Make your DIY work easier. 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.