There is a water level sensor probe at the bottom of the solar floating aeration pump. It will start to work when it is placed in water. It will not work when it is out of water. When the battery is used up, the product will continue to work after being charged to 3.5V in the sun. Features: [Solar Power]Solar energy powered, no electricity needed, just the sunshine, energy-saving, and environmentally friendly product. [Working Mode]The oxygen pump works for 10s and stops for 10s. It is recommended to install in a small family pond, and a small area of the pond to increase oxygen. [Easy to Use]Connect the tube and the air stone put it in the water, the aerator pump will float in the water and work. [Low Noise]Stable and silent oxygen pump, the volume is less than 60 decibels, and the air output is 0.8 liters/minute. [With Battery]Built-in 3.7V 2200mAh lithium battery to store power, so the oxygen pump can also work at night. Specifications: Material: ABS Color: Black Battery: 1*3.7V 2200mAh Lithium Battery Solar Panel: 6V/2.5W PET Monocrystalline silicon Lifetime10000 Hours Solar Panel Shape: Round Rated Voltage: 5V Noise: Less than 60dB Max Flow: 0.8Lmin Working mode: Works for 10s and stops for 10s Waterproof: IP65 Working time: 16h Charging time: 5-6h Working temperature: -10~45 Occasion: Small Pond Solar Panel Diameter: 18cm / 7.08inch Package Size: 19*19*6cm / 7.48*7.48*2.36inch Package Weight: 400g / 0.88lb Package List: 1 * Solar Aerator Pump 1 * Bubble Stone 1 * Pipe Note: 1. Working power of the solar panel will be influenced by weather, location, etc. 2. Don't make the pump work without water, or its lifespan will be shortened. 3. Clean the pump regularly. If it's a duty, it will stop working. 4. The packing contains small parts so please keep them away from children and pets.(danger of suffocation)