The more oxygen it gets, the hotter it burns
It doesn't make a visible flame, so you may need to wait a few seconds or even minutes to be sure it is lighted
This warmer has added an extra layer of constant heat production and it works for me
The fluid lasts longer then it suppose to based on the included plastic filling canteen's markings, I put 6 hours in I get 8-9 hours of use
Zippo Lighter Fluid as I expected it would use
Then replace the catalytic converter on the hand warmer