Winter is here, and typically I have problems with the cold. Not that my feet are terribly cold, but the skin tends to tighten around my residual toes and it hurts when I walk.
My solution? Heated socks - specifically the Lenz Heat Sock 5.0 socks.
You can buy the socks ($75 a pair in my area) and the battery packs + USB charger separately, or buy a complete kit with everything in the box.
They're not cheap, and you have to wash the socks by hand delicately, and avoid pulling too hard on them when you put them on. But they really do help with the cold.
Here's what my (old) pair looks like on my feet:
Each sock is connected to one battery pack at knee level, and then the sock is folded over the battery pack to hold everything in place.
The batteries have 3 heating levels, and they last 7 to 8 hours on low. On high, they're depleted in 2 or 3 hours, but they really do get hot: I cracked out the thermal camera and measured 110 degrees on top of my stumps (43 C) and 95 under my stumps (35 C).
And here's what that looks like on the thermal images:
If you have a foot amputation and you struggle with the cold, I highly recommend these socks.
And I think they might help you if you have a below-elbow amputation too, because a friend of mine with Reynaud's disease wears them on her hands and she swears by them too. She says it's lighter and more effective than the thick heated gloves sold for skiing, and she can wear thin mitts over them, which she prefers when it's not very cold outside.
She has the smallest size socks in the lineup, and they sure looks like they could work on a residual upper limb.