Hammer 30
Hammer Concrete Cleaner: Apply HAMMER-30 solution with a stiff brush and allow to stand for 5 to 10 minutes. Brush loosened concrete off. Extremely thick concrete may require a second application. For very light concrete HAMMER-30 may be diluted with up to 5 parts water. Rinse with hose or brush, flushing thoroughly with clear water until all suds are gone. Be sure surface is rinsed well before chemical dries.