Features: This self tightening drill chuck is perfect for drilling holes in ABS boards, light wood boards, paperboards and more. The grinder clip is compatiblewith 0.5 3.0mm drill bits and can be used as a hand drill or electric drill. This product is suitable for DIY enthusiasts, carpenters, electricians and other professionals. It can be used in various scenarios such as home decoration, furniture repair, circuit board drilling and more. With its copper material, this product is durable and long lasting. Specifications: Material:Brass Optional Aperture Size:approx 2.35mm/ 3.17mm/ 4.05mm/ 5.05mm/2mm Copper Drill Clamp Drill Bits Size approx:0.5mm 1.0mm 1.5mm 2.3mm 3mm Can be used for ABS boards, light wood boards, cardboard punching holes Note: Please allow 0-1cm error due to manual measurement. please make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you Package includes: 1 Set Brass Clamp Set