APIBDT250 This disc like de-icer by Allied Precision, Inc. is designed to be completely submerged in any birdbath. It has a built in thermostat so it only runs when the water's temperature is below 35 degrees Fahrenheit and it includes an adjustable clamp so you can attach the de-icer directly to the water container. The de-icer should be positioned in the center of the birdbath with the power cord draped over the side. Run a fully grounded extension cord to the unit and always keep the unit clean by removing any lime build up. Features: -250 watt cast aluminum birdbath de-icer with 6' cord. -Cast aluminum construction. -Includes stainless steel guard. -Includes cord chew protector. -Enjoy your backyard friends all year long.