This product is a self centering drill bit. It is made of solid materials. It is safe and durable. It can serve you for a long time without being easily . It is an excellent self centering drill bit that can bring you more convenience, allowing you to have comfortable experience. Features -Color:Black -Material:Alloy, high carbon steel -Size:9.80X1.80X1.80cm/3.85X0.71X0.71in - Made with alloy and high carbon steel, high hardness, durable and great drilling performance. - When opening the hole, please adjust it according to the hardness of the wood. - The positioning is convenient and will not move, and the wood chips will be automatically discharged from the holes on both sides of the drill bit, and the drill bit will not be stuck. - Drilling accessories are very suitable for DIY hinge installation work and will bring you more convenience. - Simple in structure, easy to use, not easy to deform, you can use it with confidence. Package list: 1 x 1/4 inch drill bit 1 x 5mm drill bit