Features:_x000D_ _x000D_ 100% High quality and Brand new. _x000D_ This product uses advanced natural diamond material, with a special enhanced coagulation treatment from electroplating sand suction hole neat, smooth, no broken edges, etc., is the efficient construction, installation hole of choice. _x000D_ This section openings optimum glass openings, tiles can be opened, but just open a few holes in the opening, please add water, it will extend the life. _x000D_ The product is installed on a professional drill or electric drill, bench drill. Rpm 800-1000 rpm or so, you must add water cooling holes during operation. _x000D_ Use: apply to work openings fast glass, plastic sheeting, wood and other products. _x000D_ _x000D_ Size:_x000D_ 3mm / 5mm / 6mm / 8mm / 10mm / 12mm / 16mm / 18mm / 20mm / 30mm / 40mm / 50mm / 60mm / 70mm _x000D_ _x000D_ Package Includes:_x000D_ 14pcs Diamond Coated Hole Saw Drill Bits_x000D_ _x000D_ NOTE:_x000D_ 1 After opening installation, commissioning idling should observe whether the beating, then normal operation, the best results_x000D_ 2 Into the hole to have a smooth time, please do not exert pressure on the side and curves spud_x000D_ 3 Have enough openings for cooling and lubrication to reduce wear and coating products off_x000D_ 4 Non occurrence of high temperature drilling dry rub, causing severe wear affect the results_x000D_ 5 The operator must wear safety protective equipment to confirm safe operation_x000D_ _x000D_ 6.Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.