【PRECISE POSITIONING】: Compared with traditional glass hole saws, our hole saws have positioning aids. The pilot drill in the center can help you make accurate positioning, ensure that the drill does not slip or get stuck, and help you drill precise holes. 【CUTTING EFFECT】: The diamond surface coating uses a sintering treatment method. The cutting edge contains diamond particles from the inside to the outside to ensure that the cutting edge is always sharp. The low cutting resistance and stable drilling ensure high-precision, smooth cuts without broken edges for optimal cutting results. 【HIGH-QUALITY MATERIAL】: Diamond hole saws are made of industrial-grade high-strength carbon steel, and the surface is nickel-plated to prevent corrosion and rust. The diamond surface coating of the drill bit makes the coating thick and uniform, and the wear resistance and service life of the hole opener are improved. The diamond surface coating on the side, which facilitates the entry of cooling water