The ADDF-002PV drinking fountain is part of the AstroPet Pisces series. The Pisces series is powered by a 5,000 mAh lithium-ion battery, so the fountain does not need to be connected to a power supply with a cable. At the same time, the device has a battery charge reminder function. When the battery is low, the indicator changes from white to red and reminds the cat owner to charge the battery. To provide clean drinking water for cats, the Pisces series drinking fountain uses high-quality filters made of activated carbon, ion exchange resin and non-woven fabric, which filter out hair, food residues etc. and prevent the spread of bacteria. Every 30 days, cat owners need to replace the filters. The drinking fountain has a reminder function for filter change. The light glows orange when the filter needs to be replaced. After the filter has been replaced, press the filter reset button for 3 seconds and the device restarts. You will also receive a free filter when purchasing the device.