[gtojohn]

I took 2 of those heaters camping in February. We were forecast for a light freeze in the morning. The smaller heater got cold enough it crawled inside my mummy bag. The bigger one was fine on top of my daughters bag. We were toasty warm, even had to unzip some. My friends in the neighboring tent told me they were so cold they couldn't sleep. Good little heaters but a lot of upkeep!