Bedrock's turbo cup wheels for smoothing and polishing applications on concrete and granite. Our turbo cup wheels are available in coarse 50/60 grit, medium 170/200, and fine 325/400 grit. Standard Marble and Granite Turbo Cup Wheels for cutting or grinding marble, granite and concrete. Standard Marble and Granite Turbo Diamond Cup Wheels are sintered turbo wheels with special contoured (convex) segments engineered for fast stock removal and to provide easy grinding and shaping of rounded surfaces, corners, angles, and edges. These Standard Marble and Granite Turbo Cup Wheels deliver maximum grinding speed with exceptional wheel life and are available in fine, medium or course grit. Standard Marble and Granite Cup Wheels are used wet or dry with angle grinders and floor grinding machines.