Features:Vacuum base guide， includes drill diameters 4， 5， 6， 7， 8， 10 and 12mmIt is designed for drilling glass， ceramic tiles， marble and slateThe diamond core drills will give a perfect cut each timeOverall Size: Approx. 9.7cm x 8cm/ 3.82" x 3.15"Package Included:1 x Diamond Core Drill Bit Vacuum Base Guide