Freesea 50 Watt Aquarium Submersible Betta Heater With Aquarium Submersible Thermometeraquarium heaterFeatures of Freesea 50 Watt Aquarium Submersible Betta Heater With Aquarium Submersible Thermometer 50 Watt Heater: This Aquarium heater is suitable for 5 to 15 gallons aquariums, Length - 68 inch,voltage 110-120V, power cord is 40 ft, please choos..