As you know, our business involves rebuilding forklift batteries. Battery acid (97% sulfuric acid) gets spilled on our unprotected concrete floors and metal equipment in the area. The acid had eaten into the concrete and metal. Your people filled the hole in the concrete then coated the concrete and metal with 429 S.T.U.F. two years ago. Much acid has been spilled since, but the 429 S.T.U.F. is not showing any signs or damage. Nothing that has been coated with 429 S.T.U.F. is damaged by the acid.