1、The float switch cannot directly control solenoid valves or high-power relays, AC contactors, etc. You should add a small relay to transition. 2、The contacts inside are made of a reed switch with very high sensitivity. 3、The action range of the two floats of the double float switch is 10mm. To control the range, you can use two float switch combinations to make a large stroke. 4、Normal water intake is the following float switch to start, the above float switch does stop work. 5、The drain is activated by the float switch above and the lower float switch stops working. Features: 1. The float switch cannot directly control solenoid valves or high-power relays, AC contactors, etc. You should add a small relay to transition. 2. The contacts inside are made of a reed switch with very high sensitivity. 3. The action range of the two floats of the double float switch is 10mm. To control the range, you can use two float switch combinations to make a large stroke. 4. Normal water intake is the following float switch to start, the above float switch does stop work. 5. The drain is activated by the float switch above and the lower float switch stops working. Specification: Condition: 100% Brand new Voltage: DC 0-110V Material: 304 Stainless steel Optional Style: Float 300mm, Float 400mm, Float 500mm Package List: 1 x Liquid Level Sensor