Because it was the factory ground, anti-shake paint was painted on the surface. When we polished and repaired the concrete at our company, we used it as a curing for the dry curing up to finish painting construction to be placed for a few weeks. Because it was used as a precision machine etc., it was like that sand, dust etc does not come out, so we used it as a curing mat so that it does not exit sand dust etc. on walking etc against the constructed concrete surface. It also has cushioning properties and is hard to slip and I am very satisfied.