My shower was starting to get a bit of standing water and was slow to drain so I ordered one of these with excitement because it looked more promising than some liquid that would just pass the clog. I inserted it into my shower drain and pulled up the most disgusting foul smelling chunk of hair, and then repeated. After about 3 passes I could actually see down my drain. You really only need to buy one of these and clean it, on the packaging it says not to reuse but it is very easy to clean and store for later use. It also worked very well on all of the sinks in my house.