The GMsound Aquarium Heater Submersible Fish Tank Water Heater Thermostat with Case is a high-quality, durable water heater that is perfect for keeping your fish tank warm and comfortable. With a suggested water volume of 15-45 gallons, this water heater provides a constant warm environment for your fish to stay healthy. The thermostat features an adjustable temperature range of 65 degrees Fahrenheit – 93 degrees Fahrenheit, and the on/off indicator light allows you to confirm whether or not the water heater is operating. The water heater also has two suction cups for attachment to the fish tank, and the polarized plug prevents electrical shock.