DESC: Mr. Heater is providing you with the perfect little (well, BIG) "buddy" for all of your indoor needs where you don't need the freezing cold. Easily hooked up to one or two 1 - 20-pound propane gas cylinders, this indoor portable heater works with 4,000 - 18,000 BTUs of power to heat up to 400 square feet at a time, insantly and effectively, to create a winter that feels a little more like spring.