Features:* The batch chuck is made of aluminum alloy.* Ergonomic design, easy to control and provides more torque.* Screws and fixtures can be inserted and removed quickly and easily.* It features heavy-duty steel with a magnetized base for excellent drill retention, while accepting all standard 6.35mm (1/4") screwdrivers and extension rods. Specifications:Product Name: Screwdriver Bit HolderMaterial: Aluminum AlloyColor: GrayLength: (Approx.) 100mmFunction: Quick Change ScrewdriversQuantity: 1PcPackage Included:1 x Screwdriver Bit HolderNote:1. Transition: 1cm=10mm=0.39 inch.2. The actual colors of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness.3. Please allow slight manual measurement deviation for the data.