18mm (3/4") Core Drill/Grinder to fit all standard glass grinders.
If you have a need to drill large holes, this is a 2-in-1 bit. A normal grinding head, but can be reversed on motor shaft to drill 18mm (3/4") hole.
Standard Grit for normal grinding.
Always wear full eye goggles when grinding. Never grind dry - always ensure a good water level.