The Mr. Heater Tough Buddy Portable Propane Heater MH9BX is a versatile and efficient heating solution for indoor spaces, with a power source of propane and a variable heat setting range of 4,000 to 9,000 BTU. Its compact size, measuring 7.7 inches in length and 13.4 inches in width, makes it easy to move and use in various areas. The radiant heating system guarantees consistent warmth, while the inclusion of an oxygen depletion sensor adds a safety feature to the design. With a minimal operating sound rating, this portable heater from Mr. Heater is a reliable and convenient choice for keeping spaces warm and comfortable.