Check the listing for details. 10Pcs 5/16" 8mm Diamond Tile Hole Saw Drill Bits Masonry Tools for Stone Glass. Color: Silver, Condition: New. Listed at 14.99 USD. JINGLING 10Pcs 5/16" inch 8mm Diamond Coated Hole Saw Drill Bits Tools for Stone Granite Marble Ceramic Product Specification Product Name: Diamond tip masonry bit, Stone cutting bits, Granite hole bit Outer Diameter: 5/16" (8mm) Inner Diameter: 0.22" (5.5mm) Shank diameter: 1/4" (6.5mm) Total length: 2.2" (55mm) Drill depth: 1-3/16" (30mm) Quantity: 10Pcs Features: Brand New & High Quality Easy to use, Good Performance and long life Excellent for making clean and accurate hole on stone, granite, marble, tile Works better with a electric drill( Excluding in this item ) Drilling speed: Drill a hole in seconds Use with water as a lubricant Quick Tips 1. Please add water for coolant and drill slowly 2. Start drill at 45 Degree to surface and align to 90 Degree as hole forms 3. Never use drills while machine is in hammer action 4. Holes Require No Futher Work As Cutting Is Clean Just a friendly reminder: Please add the water to cool the drill bit while drilling hole processThe Diamond Hole Saw Does NOT Have Center Pilot DrillThere is no need for a Pilot Drill Bit, because pilots are not safe for glass/stone.How to use a hand drill to drill holes in the glass/tile/stone?Step 1. The bit on the glass/tile/stone 45 degree, open a half-moon notch on itStep 2. Slowly up the bit to 60 degrees, and then gently drillStep 3. Reached 90 degrees, continue to drillStep 4. Drill through the glass/tile/stone finally, the technique requires a “wobble” of the drill rather that steady pressure straight on We will send out your order within 1-2 days after payment has been received and cleared Please let us know if you are looking for other accessories or hardware We Can List Any Size( Hole Diameter from 2.5mm - 200mm) & Amount Of This Product