MPI Monitor 441 Kerosene Heater The Monitor 441 runs on Crystal Clear kerosene, which is fed into the unit through a separate fuel tank. This tank is not originally supplied with the 441 and must be purchased separately. The 441 consumes fuel at different rates, depending on the heating setting used. On High, it consumes 0.319 gallons of fuel an hour, while only consuming 0.25 gallon an hour on the High-Medium setting. On the Low-Medium setting, it consumes 0.16 gallons of fuel an hour, while the Low setting provides minimal consumption at only 0.12 gallons per hour. The Monitor 441 is 26.6 inches tall, 28.7 inches wide and 13.8 inches deep. Its vent pipe hole measures 2.5 inches in diameter. When empty, the 411 weighs 82 lbs. Weight during operation varies, depending on how much fuel is in the fuel tank. The Monitor 441 promises 93 percent efficiency. ********monitorparts.us/uploads/2/9/5/1/2951437/monitor_441_manual.pdf