1、SPECIFICATIONS: This kit includes 8 hole openers with hole diameters of 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, and 68mm, to meet more drilling needs. 2、DIAMOND GRIT: These marble hole openers adopt excellent diamond grit, which is incisive and wear resistant, greatly improving drilling efficiency. 3、APPLICABLE MATERIALS: These diamond hole saws can be used to drill glass brick, marble, ceramic tile, concrete and other materials, with strong practicality. 4、FAST CHIP REMOVAL: These brazing hole openers have large chip discharge ports, with low resistance, which prevents chip blockage during drilling. 5、STORAGE BOX: This kit is equipped with a storage box for organizing and storing these hole saws, making it convenient to carry them when going out.