This tool is amazing. It grinds out cracks in cement slabs very quickly and efficiently. Needless to say, grinding cement is a VERY dusty business, so take appropriate precautions, especially if you're grinding indoors. We put up plastic sheeting around the entire area we were grinding, from ceiling to floor, hand-held a shop-vac with a hepa filter behind the grinding wheel, and wore a high quality 3M P-95 mask & face shield. The result was a nice v-shaped groove that made it easy to fill and seSee full review