Diamond Cup Wheels 1)Turbo Cup Wheel with steel core 2)Single and Double Row 3)Lasting and fast stripping 4)High Quality Diamond Cup Wheel,Grinding Wheel,Turbo Cup WheelSizes:Outer: 4.0''(100mm) / 4.5''(115mm) / 5''(125mm) / 6''(150mm) / 7''(180mm)Inner: 7/8''(22.2mm)Used for manual grinding and polishing on surfaces of natural stone and artificial stone. Diamond Turbo Cup Wheel