I have a situation where my feet and hands get uncomfortably cold. I typically would use space-heaters (when I can) while I work but that's not always allowed, nor always practical. I decided to give these socks a try.

Before I start, I will say the instructions were for a totally different "model". Mine had three heat settings denoted by 1, 2, or 3 blue "dots". Also, the instructions don't stay how to turn them on or off.

Use the cord provided and plug the usb side into a usb wall plug (or something like that). Connect both micro-USB plugs to the batteries. Blinking means they're charging. Solid color means they're charged. When you're done, put the socks on first and then plug them on. Hold down the button for about 3 seconds to turn on. Mine turns on automatically to high (three dots) but within 10 minutes automatically goes down to 2. Odd. To turn them off, hold the button again. Tapping the button toggles the heat setting.

WARMTH: There are three options for heat which I mentioned above. I see NO reason to use anything besides high. High is not that hot FOR ME. I suppose it might get hot for people whose feet generate heat. Since mine do not, I always have mine on high. If you're wearing them around your house, you'll get a warmer experience if you put another pair of socks over them.

BATTERY LIFE: about 5 hour on the high setting.

COMFORT: Weird. They're like men's dress socks. That said, my female 7.5 foot fits in them well enough... and I pull them up over my full calf. The bottoms are stiff (where the heating pad is on the ball of the foot) and they're a little awkward. I tried to wear them in knee-high boots but they didn't fit with the battery. They feel a little awkward in shoes but I suppose it's better than your feet getting cold.

All in all I'm glad I got them but I do wish they were a bit more comfortable. I can see that there's no good location for a battery pack so the pouch exists in the least obtrusive area.

I am amazed that they can function after a whirl in the washing machine but so far I've washed them twice. I do not wash them after every use. First, my feet definitely aren't sweating if I need socks to keep them warm. Second, every time I wash them I'm terrified they'll break.

If they do I'll return and update my review.

I was not sure if these would work but I’ve been in a tree stand on a deer hunt for 4 hours it’s 30 degrees and my feet are still warm. This is my first use but I can see a happy future with warm feet.

Bought these for my husband, who has gout. He had been using a heating pad to ease the pain and inflammation during a gout flare. The socks allow him to have heat wrapped around the toe area without staying tied to an electric cord. Good battery life and easy to charge.

So far, in the cold winter days, I have been helping me put a pocket in my socks to warm my hands. In principle, this is good, but of course these things have their disadvantages. The fact of putting a pocket heater in the sock is one of these disadvantages.
But when I saw these heated socks, it was time to say goodbye to my pocket warmers. A pair of socks that surround the sole of the foot and evenly heat the entire surface of the sole has an unparalleled advantage over a pocket hand warmer. It also quickly showed that these heated socks can fulfill their promise. Even if the temperature of the bicycle is significantly below zero, the feet will remain even and fully heated.
In the future, I will only use the old pocket heater as a mobile power source. I prefer to use these heated socks to warm my feet.

They are hard to get on, they fit really tight but once on they are comfortable. When my toes got cold I turned them on kept my toes warm.