Draper Silicon Carbide Bench Grinding Wheel, 150 X 20mm, - BG15020SA high quality, hard wearing silicon carbide bench grinding wheel with ultra fine grit. Suitable for sharpening tungsten carbide tip (TCT) tools and grinding non ferrous metals including alloys. Dry cutting use only. Manufactured with a 31. 75mm bore and supplied with 5 reduction rings enabling each bench grinding wheel to fit most bench grinders with a bore size between 12. 7 31. 75mm. Compatible with 19mm and 20mm wheel face Draper Bench Grinders.