Legacy Industrial's "HD39™" is an extremely reactive lithium based densifier and water-proofer. In addition to the benefits of a standard densifier this product contains an added siliconate water-proofing agent. Penetrating deep into the substrate, leaving your concrete hardened, less porous and more abrasion resistant. Mop or spray onto the substrate and watch it work. Helps to eliminate water penetration, staining, moisture/radon transmission and effloresence.This product is a green material and that means no harmful chemicals to worry about. Use this product indoors or outdoors. Can be applied using our microfiber pad/applicator over smooth interior concrete for a very even application.