COMLIFE Portable Hand Warmer, 20000mAh Electric Camping Long-Lasting Pocket Warmer & Reusable Larger Capacity Type-C Power Bank, Single/Dual-Sided Quick Heating, LED Display, Up to 14 Hours of Heat

I actually have two hand warmers, this product being the larger of the two. It’s actually gigantic, when it comes to hand warmers, and I thought it was too big. Now I changed my mind. Sometimes, when it’s really cold outside, this hand warmer is the only one I have that can keep up. It’s made with a heavy duty shell that holds a lot of latent heat. That means, it takes a little time for it to warm up, but when it does, it can transfer a lot more heat into a person’s hands. In contrast, my smaller hand warmer goes from hot to cold in a matter of a few seconds, as my hand sucks the heat out of it.To respond to other’s thoughts about the two settings- 1) one side of the warmer heats, and 2) both sides of the warmer heats. It actually works fine. the heavy duty metal shell conducts the heat from one side to the other, albeit not completely even. However, it’s a minor issue, and it works for conserving battery. The switch for changing heat levels is indeed easy to press, but so are all the other hand warmers I’ve had. It’s not a giant issue. If I feel my hand warmer becoming too cool or too warm, I know I’ve accidentally changed the heat level, and I simply fix the problem. All in all, maybe I’ve lost 10 minutes of heat on low. Not all that bad.The battery: it takes a few cycles before the battery life reaches full capacity, and this is more apparent with this hand warmer than with most others. In fact, it took a few weeks before it could stay on all day. Now, it takes forever to run down the battery, and a good number of hours to recharge the warmer. For the percent meter to reflect the correct percentage, the warmer needs to be fully charged and discharged, from full to empty, for it to establish those two points and calculate a true reading. If one didn’t know this, they’d think the battery capacity was much lower than the 20,000 Awh that it is. By far, it last longer than any other warmer I’ve ever owned, and my smaller warmer (I keep referencing) is a 10,000 Awh unit. I like it a lot, too, but it’s not the powerhouse this large hand warmer is.Listen, if you understand that you are buying a large, high capacity hand warmer, you will be happy when it turns out to be just that.

So far I give it five stars. Solid construction, easy to use and gets plenty hot.When using it let it heat up and get to temperature before you cast judgment on it, it starts to get warm within the first minute but doesn't seem to reach it's max temperature until about ten minutes mabey a little less because I didn't time it. But let me tell you when it gets hot it gets hot. I'm not the kind of person who likes luke warm handwarmers, I want it to feel as if I'm grabbing the handle on a cast iron skillet that's been cooking breakfast all morning. If this got any hotter it would burn you.Now I assume it takes about 10 minutes to get to max temperature because this is a hefty device with a large battery for a hand warmer and it takes a little while to get all that material warmed up so it stops sucking the heat away from the heating plates.To get it to reach it's max temperature sooner do not hold on to it while it is warming up, this will allow more of that heat to be focused on warming up the device and not your hands, letting it warm up in your coat pocket is a good idea to in order to trap some of that heat in. So plan ahead an get it warm.Important note : When first getting it from the delivery truck if it is cold outside the handwarmer will be cold to and all the way through so if you go and turn it on as soon as you get it it will take longer to heat up because it has to thaw itself out first which I don't recommend doing, you should always let your electronic devices come up to room temperature before charging or using and not rush it like me.All in all I think it is an excellent purchase so far, I'll see if I can remember to update my review later after I have put it through its paces though.

I got this USB heater as an alternative for my propane heater's safety mechanism prevents use at high altitude. I was camping in a 2 person 3 season tent and it got cold (30 degrees). I used the low setting and placed it in the lower part of my back and it kept me warm. I used a comforter and I can only imagine it working better in a sleeping bag. In about 7 hours it went from 100%-60%. On my second night, it stopped after about 5 hours, stuck at 30%. It seemed to auto shut off at that level no matter what. I also tried to use the power bank features and it also auto shut off. Before my trip I had completely drained the battery to zero and charge back to 100% so I was not ready for it to cut off like that. When I got back home I was able to charge it back to 100% and it was heating and working as normal. Will have to further test to see how if it does it again.I also found the perfect case (see pic) for it: https://amzn.to/2JbNRFf - It fits perfect and plenty of room for the charging cord.

I initially purchased this as a gift for my mum but it's so heavy I thought she would never be willing to carry this monster around with her. (weight is 485 grams or 1.07 lbs) Its about 6.5"x3.25"x1.25" tall. I ended up keeping it for myself & buying a smaller one for my mum. It seems durable & the outside hasn't gotten chips or worn down like some other brands I've owned. It only has 2 heat setting so that's kind of lame but the lower heat setting is still rather warm.If you don't mind it being a hefty boi or if you've got big hands or big heating needs, this is probably a good match for you.