The Sinking De-Icer operates at the bottom of your pond where it is less likely to be disturbed by fish. Keeping your pond open allows fresh oxygen into your pond during all season, keeping your fish healthy. Thermostatic control coupled with thermal feedback protects the unit from overheating. The thermostat is positioned above the heating element to ensure safety in low-water conditions. Recommended for 100-300 gallons of water. Includes durable metal guard to protect rubber and plastic-lined ponds. Includes 15-foot cord with anti-rub protector. cULus Listed. 1500 Watts, 120 Volts, 60 Hz. One year warranty.