1. Material: chrome vanadium alloy steel 2. Surface treatment: chrome plating 3. Size: 6.35 mm standard handle 4. Weight: 160mm 142g, 60mm 82g 5. 160 mm armrests are removable 6. Tools with high speed such as electric wrenches are disabled 7. Compatible models: hand electric drill / rechargeable drill / driver / wind approved electric batch