Ortho, 1.33 Gallon, Ready To Use, Groundclear Vegetation Killer Refill, is formulated to kill weeds and grasses and prevent new growth for up to 1 year. To use this refill, simply attach a Comfort Wand from the original Ortho GroundClear Year Long Vegetation Killer ready-to-use spray bottle. Use on areas where weeds are not desired, including driveways, sidewalks, gravel areas, rock and desert landscapes, under decks, on parking areas, along fences and curbs, and in unplanted areas. The fast-acting formula should be applied to actively growing weeds. You’ll see visible results in an hour with Ortho GroundClear Year Long Vegetation Killer. Treats up to 400 sq. ft. Active ingredients: Imazapyr, isopropylamine salt: 0.09%, Pelargonic Acid and arelated fatty acids: 2.00%