Specification: 10pcs/set. This kit contains 7pcs diamond core drill bits(6/6/8/19/35/50/65mm); 1pc 4/5" diamond finger bit; 1pc 2" diamond chamfer bit; 1pc connect 5/8"-11 thread to SDS adapter. Application: EXFEIN core drill bits are used to drilling holes; finger bit for enlarging holes; chamfer bit for trimming holes; For porcelain ceramic tile marble granite, etc. Dry or wet use. Wet drilling with less debris for longer life Machine: 5/8" arbor angle grinder. Recommended speed 6000RPM; Maximum speed 11000RPM. sds adapter in this kit can be attached to a drill bit with a 5/8" fitting so that the drill bit can be attached to your drill machine with sds-plus thread. If you are using this kit on a hand drill, make sure that the drilling speed does not go below 2000 RPM. and do not use the impact drill mode. Durability: Vacuum Brazed technology combines a high-quality steel matrix with diamonds in a scientific ratio and provides high efficient working performance and longer service life. Fast drilling: Lightning teeth has wide chip removal slots, dust can be quickly discharged when drilling, not easy to be clogged.