Fully Automatic Water Level Control Float Valve, Automatic Closing, Mini Float Valve, No Power Required, Automatic Water Level Controller for Water Tanks and Towers Fully Automatic Water Level Control Float Valve, Automatic Closing, Mini Float Valve, No Power Required, Automatic Water Level Controller for Water Tanks and Towers Working Principle The internal float valve allows water flow until the set water level is reached. When the water level reaches the set level, the float valve is pushed upwards by buoyancy, thus stopping the water flow. When the water level begins to drop, the valve reopens, and the water flow resumes. When the water level drops below the valve position, the float valve automatically fills your water tank, water tower, livestock drinker, or animal drinker. It automatically stops filling when the water level is below the valve position, so the valve closes when the water level reaches the internal float. [Easy to Install] This is a mini float valve with a small ball size for easy installation. It uses a 1/2-inch external thread and BSP pipe thread. The external thread is relatively long and compatible with most BSP threaded connections. If your pipe thread is NPT, simply wrap some PTFE tape around the external thread for perfect compatibility. The internal float valve (no power required) allows water to flow until the set water level is reached. When the water level reaches the set value, the float valve is pushed upwards by buoyancy, thus stopping the flow. When the water level begins to drop, the valve reopens, and the flow resumes, thus requiring no power. It is used to maintain water levels in garden waterfalls, fountains, ditches, and garden works. It can also be used for automatically shutting off swimming pools, chicken coops, automatic drinkers, livestock watering during droughts, outdoor rainwater collection bins, etc. The float valve operates within a water pressure range of 10 psi to 150 psi. If the water pressure is too low or too high, the float valve will not function and may stop working or be damaged. Operating temperature: 0~60 degrees Celsius. [Easy to maintain] The float valve comes with a filter, which must be installed at the inlet to prevent grit from clogging the float. The valve body is made of nylon and fitted with stainless steel screws, ensuring it will never rust and is extremely safe. [Note] If you are using any type of automatic filler float valve indoors, please ensure it is equipped with an emergency overflow system. It is recommended to set the water flow rate to the minimum required to maintain full water level.