[Function] Used in conjunction with vent line, allow your tank to breath and not build up pressure or vacuum. [Package] Vent valve replacement for tanks. Kit can be split up, which shows in pic. [Material] Made of sturdy metal, long service time than other materials. [Installation] May take some time to install, make sure to be vertical, and check ball must be in bottom fitting. [Note] Suggest to refer to the installation video when operate., Manufacturer: Akfldms