"¦ also works great, better than a big heating pad, on muscles, joints, injuries, stiffness. Even things like jaw clenching, TMJ, sinus and ear pain. You can even rest your neck or wrist by it, and tuck it into weird places like the crook of your collarbone, or in a hood hanging between your shoulderblades. Just be careful to let air get to it, and put a layer of thin fabric between the heat and surfaces, or the heat and your skin anywhere except your palms, which can usually take more heat. You could even try using it as a boot warmer (just make sure to remove it) before going outside. Low setting isn't as hot as HotHands, and we are thankful for that. High is about the same temp as HotHands. If you want heat on a larger area than your hands, try putting it in the middle and move it a bit from time to time. It does get very hot for indoors, low setting is almost too much for us at room temp without fabric between heat and skin. Temp goes up and down in gentle waves, but this is a good thing, keeps your skin from getting too hot from constant heat, keeps the wires safe, and it makes the battery last longer. It arrived with a battery partway full, and that lasted at least a couple hours, after a really fast, hot warmup, while we played and tested it. We think it will last at least the described length, maybe 8 hours at room temp. Warmup after several tries was still very fast and hot, just a couple minutes, not even five. Color is as pictured. Button and lights work as described, easy to figure out if you dont want to read the manual. Plastic strips around the sides make it easier to handle the smooth oval shape. Power cord works and ports are as described. You can use your device's power cord instead of this one to charge off of this device if this device's port isnt the right kind for yours.

We feel a few things could be better. Power cord is very short, maybe 8 inches, and we like long cords. But some people like short ones, less to tangle. We also wonder if the on-off button, which sticks out a bit, could get bumped on inside a packed bag, tight mittens, or a tight pocket. We have bumped the temp too high by accident in our hands. And, the one we were sent DOES heat up and the button DOES work while charging, though the manual, read with a magnifier, says neither should. The lights turn pinkish purplish when it is heating and charging at the same time. Hopefully, this is safe for the wires. But overall, this is way better than HotHands or a heating pad, so far.

I'm a nurse in the operating room, it kept my hands nice and toasty. I love the fact that I can wipe it off with sanitizing cloths

This is a great product however the description does not allow you to know that it's a European product which needs a reverse charger. It comes with the cord but not the adapter.

This product works so well and is surprisingly hot on the top setting. Love it. Showed it to all my coworkers and they bought some too. Game changer when you're a massage therapist who has cold hands normally!

I'm just waiting for the price to dip on Amazon so I can buy another one and a gift for my aunt. The material is very smooth and a pleasure to hold. The compact size fits nicely in a pocket. I am glad for the tie-on strap and do use it sometimes. The powder coating is a slippery surface and is holding up well. I use this product every day since getting it and the only time I don't have it on me is when it is charging. The battery lasts about 3 - 4 hours on low. I rarely take it off the low setting, which is perfect. The medium is too hot for me to handle.

I toss this in my bed before I get in to prewarm the sheets. I also warm my socks with it before putting them on. If I'm working outside, it's nice to stop periodically and hold on to it to get my fingers warmed up -- especially good if you have to do any work on a car outdoors in the cold. I have mild Reynaud's in my fingers, and this heater keeps the worst of it from happening.

Do note that it power cycles a bit -- sometimes getting warmer for 10 - 20 seconds. This is totally normal. My other handwarmer does the same thing. I wish I had gotten a 2nd karacel one instead of the other one I tried.

One down side is the blue indicator LEDs blink while it is charging. So I cannot charge it in my bedroom at night, which is the logical time/place to charge it, because the blinking is super annoying. That is the only thing I would change about its design. When it is in use, the red LEDs light up - 1, 2, or 3, depending on the heat setting. They don't blink, but they are constantly on.

Great product.