Roundup Fast Acting Ready to Use is a glyphosate based weedkiller that will kill the root of the plant causing the rest of the plant to die. It has a fast acting formula to speed this process up. It is ina reafdy to use formula so you can spray straight away and see results in 1-2 days. Roundup Fast Acting comes in a 1lt bottle, a 2.5lt bottle or a 2.5lt pump srayer. Use weed killer products safely. Always read the label and product information before use.