Aqualine's plastic float valve detects elevation changes in a liquid-free surface, then opening and closing valves accordingly. When levels of water rise, the durable plastic float will rise with it. This plastic float will maintain levels in cold water header tanks. This action then regulates the hot water system's pressure. Aqualine's plastic float valve is suitable for domestic plumbing needs. The MPT plastic float valve with a round ball from Aqualine detects changes in elevation, opening, and closing valves accordingly. The float valve is used for maintaining the level in the cold water header tank. This regulation then controls the pressure of the hot water system.