Features:- This is a brand new item- This diamond coated core drill bit removes a complete circle from glass， tiles， marble， granite， ceramic or other materials and only needs water for lubrication- Can be used with a standard electric drill ( Excluding in this item )- Easy to use， high quality，good performance， long life- Excellent for making clean and accurate hole on glass ， tile and marble- Always use lubrication (water )， otherwise the diamond core drill will burn- Start your hole diagonally， make a round trace and then hold drill straight- Size:6mm outside diameter， 5.4mm shank ， can drill 35mm depth8mm outside diameter， 6.4mm shank， can drill 30mm depth10mm outside diameter， 6.5mm shank， can drill 30mm depth12mm outside diameter， 6mm shank， can drill 30mm depth14mm outside diameter， 7mm shank， can drill 30mm depth16mm outside diameter， 6.4mm shank， can drill 30mm depth18mm outside diameter， 8.2mm shank， can drill 30mm depth20mm outside diameter， 8mm shank， can drill 30mm depth22mm outside diameter， 8mm shank， can drill 30mm depth25mm outside diameter， 9mm shank， can drill 30mm depth26mm outside diameter， 9mm shank， can drill 30mm depth28mm outside diameter， 9mm shank， can drill 30mm depth30mm outside diameter， 9mm shank， can drill 30mm depth40mm outside diameter， 9mm shank， can drill 30mm depth50mm outside diameter， 9mm shank， can drill 30mm depth Package Includes:1 x 15pcs Diamond Coated Hole Saw Drill Bits