Filter floss with a coarse structure for catching the first dirt Excellent for biological filtration. Made from 1A quality nylon fibers, is very elastic and has a long service life. Universal filter floss with high dirt absorption and large filter capacity. The water permeability is high and the wadding can be rinsed out several times. Tip: the performance of filter floss decreases after one season. It is therefore best to replace them in spring.