depends on the outside temp. Honestly I just shove my beardie in my jacket or snowsuit, but I have a good one so she don't feel a thing even if it's below zero. Gecko would be too fragile. Stick a small cricket keeper with a cold pack warmed to about 90 in a igloo cooler. The cricket keeper will keep the gecko from escaping or getting trapped in the lid (if you got the kind with the button on the side to open it) and keep the pack separate from the gecko.