Wet Welded Diamond Drilling Core Bits for drilling hard granite, marble Feature: 1. Wet drilling, Multi purpose for drilling hard granite, marble, engineering stone, concrete, brick..... 2. Solid drilling bits less chips, not easy to break off 3. High Grade and Special bond matrix extends drilling life and improve the working efficiency Specification: Diameter 6MM, 8MM, 10MM (Solid segments), 12MM, 14MM (Crown segments) Total length: 75MM (6/8/10) or 100MM (12MM & above), Thread: M14 or 5/8-11 Quatity: 2pcs only Operation tips: 1. Fix it on angle grinder tightly and rightly 2. Turn on the angle grinder and let the core bits rotating in the air to check if there is balance problem. 3. Hold the machine very steadily and give gentle pressure 4. Start drilling as per following instructions: 1) place the drill at a 30 degree angle, it will help to position 2) When Drilling the material till the hole start to form 3) Bring the drill up into upright position slowly then keep drilling vertically. 5. Do not give too much pressure or sway the core bits when working. ================THE END================ available diameter: 6mm, 8mm, 10mm, 12mm, 14mm, 18mm, 20mm, 25mm, 32mm, 35mm, 38mm, 50mm, 58mm, 65mmm, 75mm, 102mm