The Calcium Filter protects the misting system in two ways; it stops solid sediments, as small as 5 microns, from passing through the system, clogging the nozzle orifice. A mist filter helps to prolong the life of the mist nozzle and inhibits nozzle clogging. It is suggested the filter be replaced annually for best results. The unit is just over 7 1/2" and has a female hose swivel at one end and male hose at the other end.Contents of the filter contain: 54% Hexametaphosphate, 44% Polyproplyene.