Mr Heater's Original Series Triple Tank Top Heater F242900 allows operation of 1, 2 or 3 burners at a time and produces up to 45,000 BTUs of heat by directly connecting to a 20 lb bulk propane tank / cylinder. A hi / med / low regulator allows you to decide how much heat is produced and 2 safety shutoffs automatically turns the off the heater when there is a loss of flame. There are no moving parts within this heater providing quiet operation and requires minimum maintenance. The F242900 is for outdoor use only and is ideal for construction sites, thawing / heating purposes, vehicle maintenance, warehouse loading docks, outdoor jobs or camp sites. Tank / Cylinder Not Included.