Resolva Pro Xtra Tough Weedkiller Ready to Use is a systemic weedkiller. It is ideal for controlling annual and deep-rooted perennial weeds. It delivers effective and quick results, even on tough weeds, so they don’t come back. Kills tough weeds and roots with fast systemic action, visible effects in 24 hours. The 1L bottle has a unique non-drip trigger and contains glyphosate.