Do those things take up a lot of power? I'm wondering if a portable battery with an AC outlet like this can power those things: http://ecx.images-amazon.com/images/I/41sg0N%2Bq%2BRL.jpg
I know people usually charge them through the Car DC cigarette charger port, but mines is broken so I'm wondering if it's worth fixing. I don't use that port for anything else. I'd rather just buy a portable battery because I have other uses for them.
Is there a consensus on what the best ones are? Or are there ones with an internal battery?
I have Zip fit liners and the idea of preheating them does sound pretty great for not having do a few runs to get them to mold to your ankles.
This is a hot gear bag in case you don't know what I'm talking about: http://images.evo.com/imgp/enlarge/46647/314620/hot-gear-classic-ski-boot-bag-black.jpg
It's suppose to preheat your liners so they fit better right off the bat.