SUNSKY 5PCS Ceramic Glass Hole Opener Domestic Marble Hole Puncher, Punch Diameter: 8mm 8mm

No water, all dry dozen, cooling wax, hand drill available

Cooling wax filling full, wax showing silver-white, drill body blue bright, diamond brazing bit, marking line more clear

Cooling wax filling full wax showing silver-white drill body blue bright drill bit brazing carborundum line marking more clearly

New upgrade of internal cooling wax without water, high-performance cooling wax, effective heat transfer, heat conduction fast/perfusion volume large/durable, open 30 holes can be used

New upgraded cooling groove for cutting edge chip removal, design of spiral chip removal groove for cutter head, upgrade large capacity self-cooling groove with fast chip removal, large chip removal a