Keeps water from freezing in subzero temperatures. Plug cord into outlet during the winter. Heater operates automatically. Measures 13.75 inches in diameter and 3.5 inches deep Thermostatically controlled with 40 watts of power. Keeps water from freezing during the winter. Special process used to ground the bowl in the center may show as a discoloration in the center of the bowl This is normal and necessary for good manufacturing processes.Size is 3 Quart. Dimensions are 13 X 13 X 4 UPC Code = 085045000406