 It's a powder. You mix it with water. You put it on the surface of the deck. You let it sit about 10 minutes, re-wet, and take a street broom and just agitate that rather than using a scrub brush or something along those lines, and then rinse it off. By the way, I know a lot of people go, oh, I got to redo my deck. I'm going to sand it and pressure wash it.