Safe n' Easy Oil/Grease Cleaner is a highly concentrated, biodegradable cleaning product and has specifically been formulated to clean motor oil, grease and heavy soils from concrete and asphalt surfaces. This product can also be used to clean walkways, barbecue grills, lawn and playground equipment and a variety of other surfaces. Safe n' Easy Oil/Grease Remover has been engineered to actually penetrate beneath the surface into porous concrete, asphalt and masonry surfaces. It does not sit on top of surfaces like other cleaners. Usual dwell time is three hours and it can then be either pressure washed or hosed off. No scrubbing is required.