The Rock which should a solid Field Rock, is mass so it holds the heat for an extended period of time.<br>option 1. leave on all night<br>2. turn off heater just as you get into bed, leave rock on heater cage<br>3. warm up rock, put under the covers, maybe in a roasting pan or an old frying pan with a lid, warm up the sleeping platform, put back on the heater, re-warm<br>turn off and let it dissipate the heat longer into the night. <br><br>sport cat/black cat, too many names, look on the box, find the info, lowest and highest btu as well as how long it lasts on 1 gal container. One of the lasts 14hrs now, the one I use lasts 9-12hrs. Will buy a new one on sale soon, or in the pre-fall sales. <br>.. Will post a pic soon, will go and take a photo of my setup, now it is in Box truck, has lots more room but I did do a few tests to see how hot it gets behind and above the heater setup, before sleeping. <br><br>When it is around 6-10 Celsius I turn it off overnight as it is warm enough to sleep in my insulated home. The big trick is to make sure you do not open any doors 1 hr before bed, warm up with your body and heater, turn off at bed time. <br><br>So, why leave it on, I did try to turn off when not there a few times, but it takes 2-3 days for the mass of the vehicle and objects in it to warm up in the middle of winter. Too cold too long and too many problems. I have mine connected to a 100lb tank and it lasts a month and a week when only using the small heater. The Big Buddy would consume the tank in 3 weeks as it used 20lb propane tank in 4-5 days or so.<br>