Never use Hot Hands. They burn too fast, too hot, and displace oxygen just as quickly. They get much hotter than shipping packs. Not to mention, they don't last as long. They won't last 24 hrs, that's for sure. Most won't even last 12 hrs. Hot hands are typically meant to put in your gloves for snowy weather.
And unfortunately, many snakes have overheated in boxes with hot hands.
A reptile shipping pack should not get hot enough to melt or burn a bag. I'm really doubting that breeder's word.
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