Filter Flosser is a well made, inexpensive, effective and ergonomically designed cartridge filter cleaning tool for the pool & hot tub industry. The main reason that Filter Flosser works so well is that the nozzle provides an evenly dispersed water spray that gets in between the pleats of the cartridge filter acting like a water pic; it also generates a water and air agitation action that works out the dirt deposits down deep in the cartridge. You can also use this product in three distinct ways for best cleaning action.