When I take any of my girls out and about (which I do often) I use one of those microwavable heating pads. Okay let me see if I can explain it more. We bought it at Bath and Body works (so this one is all nice, lol and now I use it for leo transport) and it's fabric with some type of "stuff" inside. You put it in the microwave for a few minutes (1-2) and it warms up. It's supposed to wrap around your neck and ease sore muscles (I'll post a pic too) but I put it inside of one of those critter keepers, the plastic things with small vents on the lid. And I cover the top of the critter keeper with a cotton shirt. So air can come in, but for the most part the container stays nice and cozy warm. It's a lot less complicated that I just tried to explain it. Now as far as traveling far distances, you would just have to find a microwave to reheat something like that once it started to get cold. But anything that is similar to what I'm talking about works great. It isn't too hot to hurt them, but it keeps them warm, and with the shirt on top, it more or less insulates the container to keep a pretty constant temperature for a little while. Hope that made sense!
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-Kristen
0.6 Leopard Gecko (Buttercup, Beaker, Beauty, Blaze, Bubbles, Blinkers, and Squiggles {yeah I broke with the B's, but her head has black squiggles on it!!!})
1.1 Fat Tail Gecko (Bell and Bowser!)
0.1 Deformed Leopard Gecko (Gimpy)
Proud owner and operator of a Powerbook G4! Why use windows, when I can use Panther? It even sounds better.