Is premixed, professional grade, ready-to-use liquid. It easily removes tough rust stains, simply spray on, rinse, and walk away. It can be used on concrete and asphalt driveways, sidewalks, decks, patios, fencing, docks, plastic, fiberglass, boats, around the pool, and much more. Ready-to-use outdoor liquid removes most stains without scrubbing. Plant safe with normal application. Great for sprinkler rust stains. Size: 128 Oz. Type: Liquid Septic System Safe: No