This refill contains enough Roundup for your Pump 'n Go sprayer system. Premixed for easy and effective weed control, this weed killer starts to work in hours. For use on unwanted vegetation, it is absorbed by the leaves and moves throughout the entire plant, above and below ground, to destroy annual and deep rooted perennial weeds, including grasses, dandelions, docks, bindweed and thistles. It is inactivated immediately on contact with soil and is then broken down by soil micro-organisms, to allow replanting. Do not use on lawns or other wanted plants.