Enjoy your above ground pool past the end of summer! The Flowclear 4 kW Pool Heater is an energy-efficient way to regulate the temperature, so you can keep the water nice and warm as outdoor temperatures cool down. The anti-corrosion titanium heat exchanger is built to last and is IPX4 waterproof for extra safety. This pool heater is easy to install and simple to use, with an included water sensor power switch. This pool heating system also features an internal protection function that prevents the heater from running in temperatures colder than 12? C, avoiding any damage to the inner system from overworking itself. Pool Compatibility:This pool heater is great for above ground pools up to 30, 000 L (7, 925 gal.) in water capacity, and is compatible with cartridge or sand filter pumps with flow rates of 2, 006 L/h (530 gal./h) and above. Compatible with most above ground pools on the market, this set includes adapters for both 3.2 cm (1.25") and 3.8 cm (1.5") filter pump connectors.