1、M14 Female Thread: The drill bit is designed with M14 female thread, with slip proof handle, has large torsion and high capacity 2、High Performance: These hole saws drill holes neatly and smoothly without broken edges, no need to add water, which is sharpness and wear resistant, suitable for marble, glass, ceramic, tiles, etc. 3、Diamond Material: The hole saw is made of fine natural diamond powder, the cutting blade is made of excellent diamond, which is sturdy and durable, has more effective performance than traditional carbide or bimetal hole saws 4、Thickened Emery Coating: The drill bit is uniformly coated with thickened emery, improves wear resistance and service life, has stable performance 5、Rust and Corrosion Resistant: The drill bit kit equipped with an aluminum box with high end appearance, which is rust and corrosion resistant for storing the drill bits