DOMETIC CORPORATION 1" Sanigard Holding Tank Vent Filter 309310006 1 in. Sanigard Holding Tank Vent Filter Stops odors that escape from the holding tank vent Contains odor-removing filter materials to keep boat smelling clean and pleasant Each cartridge lasts for an entire season and is easily replaced for a fresh start Includes hose adapters Does not include mounting bracket-use SEA309310005 for 1" filter with mounting bracket