bubbling or gurgling sounds, low maintenance, no need to clean the heating element, two power settings of high and low, variable humidistat and re-fill indicator light, automatic shutoff when tank is empty, PTC ceramic heating element and absorption sleeve, 1.5 gallon tank capacity, 500 square foot coverage, 15 hours run time on high, patented warm wicking vapor system, 120V, 60Hz, 380W.