I've never ordered crix in winter so don't know the kind you are talking about and can't comment on them. However, one of the ladies in my herp club brought a snake to a meeting and had a heated disk in with him. You can buy them at Target I guess, in with the kitchen stuff. You microwave it to warm it. The longer you nuke it the warmer it gets, so you'd have to play around to see how long it takes to get a nice warm temp that's not too hot. It holds it's heat for hours and works great for taking animals out on cold days. I plan to get some. It's about the size of a small dish and is round and flat. There are also reusable ones you can buy to use as hand warmers but they get very hot and don't last as long.
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0.1 Cat(Mia)
5.1 Ferrets(Wolf, Shadow, Roland, Verdell, Boo, Sullivan)
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1.0 Malagasy Blonde Hognose(Wilbur)
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