【PACKAGE INCLUDE】8pcs/box: 6pcs drill bits: diameter (20/25/35/50/75/100mm), 5/8"-11 Thread, diamond height 10mm, diamond grit #35/40; 1pc 50mm beveling chamfer bit, working depth: 20mm, diamond grit #80/100 ; 1pc SDS shank adapter. 【APPLICATION】Dry or wet drilling/milling for porcelain tile, granite, marble, stone, masonry, brick... Wet drilling/milling can prolong the service life. 【TECHNOLOGY】Made of high quality diamond and steel by vacuum brazed diamond technology, provide very high efficiency, drilling faster, durable and sturdy. 【FEATURES】Fast and smooth drilling, long lifetime, less chipping. Lightening shape design to fast remove chips, improve drilling efficiency and wear resistance of hole drill. 【MACHINE】Recommended RPM is 6000; Maximum RPM is 11000. Widely used in Angle Grinder. The 100mm core drill bit's recommended RPM: 3000-6000RPM. If you want to use electric drill or other machine, you can use SDS Shank Adapter. Using in Hand Drill, Cordless Drill or Bench Drill, Recommended RPM: 2000-5000RPM. The faster the speed, the longer the service life.