1Firstly position at an oblique angle of 45 degree, then drill the hole vertically (note low speed operation about 800-1000rpm). 2Fit for bench drill, power drill and machine tools with drilling function but not for impact drill (Cannot use the impact function to drill). 3Suitable for drilling on stone, ceramic, vitrified tile, glass, etc. You need to constantly adding water to cool in the process of drilling. 4The cutting edges of drill bit adopts section design for reduced cutting resistance, also conductive to chip removal. 5Universal triangle drill shank can effectively prevent skidding during drilling and bear more torque. 6Long oval hole on the drill bit is more conductive to the discharge of the chippings.Specification(Optional)TotalLengthHandleLengthHandleDiameterWorkingDepth25mm82mm/3.23in25mm/0.98in9.4mm/0.37in58mm/2.28in30mm83mm/3.27in25mm/0.98in9.4mm/0.37in58mm/2.28in32mm82mm/3.23in25mm/0.98in9.4mm/0.37in58mm/2.28in35mm83mm/3.27in25mm/0.98in9.4mm/0.37in58mm/2.28in38mm83mm/3.27in25mm/0.98in9.4mm/0.37in58mm/2.28in 1 x Drill Bit Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.