Used two of the Vevor diesel heaters on an elk hunting trip this last week. Ran one non-stop for a week. Had it on lowest setting of 1 and it was plenty warm enough to keep a popup pickup trailer toasty and from freezing. I set up a second one to keep an uninsulated cargo trailer warm for sleeping area. Setting of 3 was perfect. At 3 it used about a gallon in 12 hours. On lowest setting of 1 it used about a quart in 12 hours... amazingly efficient. Weather was about 15 at night and 40 during the day. Its so much better heat than older propane heaters that I used to fight the condensation in tents with. The indirect heat is dry and has no odors. As soon as I finish review Im buying another 2. Only think thats odd is the exhaust and intake vent through tubes on the bottom. I made a wood base to mount them on so they could set on the ground and hook onto my ladder on Popup camper. Also I ordered longer insulated 3" vent tubes on Amazon to direct to a vent i installed.