Features: The product is based on the real needs of plants and pumping of family and well developed. The product pool is based on the detection (water tower) for controlling the level of high current relays water to achieve control. With a small, simple wiring, low power consumption, high capacity switching. strong anti-interference function and high stability. Open automatically when you can stable pool (water tower) pumping water pumps. the pump automatically stops pumping to the full. This product can be used in the for tank pond water, garage, basement flooding rains where automatic drainage. Specifications: Material:PCB Size: As Picture Shown Note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings. Package includes: 1 x Water Level Detection Sensor