Celestron – Elements ThermoCharge 10 Hand Warmer and USB Power Bank – Scent-Free, Chemical-Free Heat – Rechargeable Hand Warmer and Phone Charger – 2-in-1 Tactical Outdoor Gear – Ergonomic Design

Ok. I purchased this for a recent winter trip to Alaska as I knew I could be in temperatures as cold as -60F. I used this in combination with the dry chemical heaters "Hot Hands" as I think there is a place for both of these technologies and this was the best fit for me.When you don't need a heater, this make very nice USB charger especially when you are going from one plane to the next and need to charge your phone and Bluetooth headphones everywhere. I purchased (2) of these devices and never ran out of power during my all day travel from FTL to ANC. Enough said for it's charging abilities.As far as a heater, well I turned them on in my front pockets of my jacket pocket and kept them on from around 10am till I arrived back to my hotel each evening. Being outside in -20f to -42f all day, you need to make sure your body is kept very warm. Wearing the proper clothing and also having the right tools to stay warm are necessary to staying alive in the untamed and unforgiving lands of Alaska. Chemical heaters in my shoes, pants pockets etc help out quite a bit, but the Celestron Elements 2-in-1 Hand Warmer did a great job in my jacket pockets keeping my hands warm when they needed a retreat from the cold. I spent 5-8 hours outdoors each day in varying temps with the coldest being -42f and the warmest being +20f. As a photographer, I need my hands to be free to control my camera settings and work the camera. In these extreme temps, you can only have your hands with thin e-tip gloves out for as much as 4-5 minutes before they are in severe pain from the cold. I would alternate hands while keeping the other warm in my pockets wrapped around my heater. So nice and toasty! Words cannot describe how good this felt and kept me from frost bite. I really can't figure another way I could have done this trip without modern technology! While I don't need this heater until my next trip, it doubles nicely as a power bank and I know everyone can always use one of those.My only complaint is the power button. It is very difficult to turn on and off as you have to press very hard to engage the mechanical button that presses the actual button on the other side of the protective cover. Even with this, I would highly recommend owning not one, but (2) of these! I also had them in my back pockets from time to time as they really warm your buns up nice when your hiking.You can extend your batteries when you are driving in your car by turning off the heaters, although keep in mind, it takes about 5-10 minutes to fully warm up so remember to turn them back on before use is needed. Charge times at night when I returned back to the hotel were a bit longer than I would have liked. If you run these down to the end which I did 2 times just as a test, you will need at least 8-10 hours to fully charge. Make sure you plug them in as soon as you return and get them ready for your next day well in advance. You will NOT want to be without these. You can also charge in your car to top off and extend use. Bring extra USB cables and 12V adapters with you for the road.Overall, you must get (2) of these per person and use the chemical heaters in addition for your feet and other pockets. If your a photographer such as myself, maybe you will want an extra for your camera bag to keep your gear warm especially your batteries so they will work well in cold temperatures. In case you don't already know, when lithium ion batteries get to cold, their capacity decreases. A fully charged lithium battery at zero degrees f, has only 50% capacity and once the battery gets too cold, they just shut down as if they were dead. Once they are warmed back up, they continue as though nothing ever happened.I hope this helps everyone and if you have any further questions, feel free to ask me.Highly recommend this product!!!

UPDATE to My 11/26/19 Bricked Review:1/8/20: I sent my bricked hand warmer in for warranty services. I had an interesting time trying to ship it since the USPS would not ship it because it was a lithium battery and required a particular sticker or label identifying it as such. The manufacturer did not send a label to affix to the package. It would have cost me roughly $3-4 to send, but received a prepaid label to ship through UPS. Just be aware of this detail.Got a replacement unit today. It works! Great, right? One problem again though...the same button issue I had in my original review where the power button on the top lid is ridiculously hard! It is impossible to turn on the device without unscrewing the lid to remove it and push the button on the inside of the device. I really don't want to have to go through the whole rigamarole of going through communication with CS about this issue...again! I'm considering just cutting the button out of the top lid. As long as I can power it on now, it will have to suffice. I am updating my review to 3 stars since the devices work, albeit not easily activated.UPDATE to My UPDATE 11/26/19: Since my last update, which is still listed below, the replacement device has since stopped working! It was used two times, TWO times, in October/November for hunting. During those two times, the device charged my phone and was also used for heat for roughly 8 hrs...all on ONE charge! That's great...BUT...then it stopped doing anything. It wouldn't charge itself, it won't heat, it won't charge a device, it won't even light up showing it was turned on. Essentially...in computer terms...it's bricked for no apparent reason. It was never dropped, never exposed to water, nothing. I have reached out to Celestron about the issue and have not heard back yet from them. It has only been 4-5 months since I purchased it, but literally used only 2 times in the field. Otherwise, it sits on my counter at home waiting to go out. This is extremely frustrating since it was a pricey purchase and lasted only 2 uses. So, I am dropping my star review accordingly.UPDATE: My original post is still listed below if you care to read. I contacted the manufacturer about the situation with the button on top and they said that it should not function that way. They sent me a new unit that was delivered within a week or so of my conversation with them. Much to my satisfaction, the new unit works as described and expected. It's still a little big, but it will come in "handy" when cold weather hunting hits. Increased my rating to 4 stars. Still thought it was a bit pricey and still not have a flashlight with it, but it will work. Thanks Celestron for your prompt service to make this right!Original Post:Disclaimer: I just received this item today and have not field tested the item in terms of it's battery life when put to the task of charging a phone and heating in a tree stand or blind.Pros: Seems pretty rugged and sturdy. Love the carabiner paracord attachment for securing to a hunting vest or belt loop or whatever. That guarantees that you aren't looking at your heat/charge source 15-20ft. below you!Cons:1) HUGE! It will definitely fill a pocket with not much room left inside for something else. This will take some getting used to. I was anticipating putting the phone in the same pocket as the power bank, but that may have to be modified given the size of this thing.2) Power button on the top is ridiculously hard to push! In order to turn on the heat, I have to take one hand on the bottom, the thumb of the other hand on top and then push together extremely hard to activate the heat option. Tried other fingers to push and still didn't work. Not sure if this is a problem with just this particular item or a model issue. Really makes it sort of inconvenient and defeats the purpose of a one hand operation. When you remove the top and push the power button, it is really easy to activate. Just wonder if something is wrong with this particular product. I've fiddled with the lid to ensure that it is seated properly, but nothing seems to fix that major problem.3) You cannot charge and heat at the same time. Pick your poison? Cold hand for a time or dead device for a time? It would be nice if that sort of detail was listed in the description of the product. Really is a bummer.Overall, for $40+, I was hoping for something that is relatively easy to use with one hand and help with keeping the phone charged in the woods and a warm trigger hand! Unfortunately, at the current time, I'm not sold yet that this particular model will do that. I may explore returning it after reading more about it to see if anyone else was experiencing the same problems. If the lid/button issue is resolved, I would imagine that this will work out ok despite its size and single-task capability. We'll have to wait and see.

I bought this for my Boy Scout grandson to take camping. He loved it. I got one to hunt with. It is very warm and good battery life.

Some negative reviews. But this is a quality product. You’ve got to charge regularly. You can’t put any battery away for six months and hope it charges after a summer of no use. One a month I charge it in off season. Secondly, running these down to zero could easily create problems. I never run it until the charge is completely gone. LiIon batteries should be kept with some minimum charge before recharge.

I bought this for my mother in law. She loves it. She was wearing a mitten on her hand to keep it warm (surgical problem required a device to be implanted in her arm but caused slower blood flow to her hand which made it cold) The hand warmer warms up in seconds and stays warm for hours. 12 hours for the “ten” model. Only thing I didn’t like was the foot long usb to sub mini cable. They didn’t even supply a cheap usb to household socket power supply. Fine, I had one hanging around and recharged the battery which is ten thousand milliamphours. Needless to say it took more than twenty four hours to charge...a bit slow. So I bought a high capacity quick charger (65 watts) and a ten foot charging cord. Ma is a happy camper now. Short waiting time (about 6 hours to charge). So when she goes to sleep we charge the hand warmer. She wakes up to a fully charged unit. This is a great device, well made by a reputable company (Celestron) if you need warm hands this is the way to go. Highly recommended.

Purchased two of these and they work great. Used these on long early morning walks with my dog. They rapidly produce heat without getting too hot. Keep them in my pockets and they keep my hands toasty warm.

Worked well for 2 months when it was cold. Has been stored in the dry and was put away fully charged. Took it out to use this winter and it wont take a charge and will not turn on. Amazon won't accept the return. I'm very disappointed with both celestron and amazon.

Unable to fully rate this product at present as I bought it for the winter months when playing golf. However on a trial run it kept warm throughout a full round without burning a hole in my pocket. Think it will be just the job in winter.

Don't buy unless you want to be stuck using micro a USB to charge it.... This is really old cable technology.... For the price they should have updated this to usb C or at least micro USB... Warms hands good enough... Could be warmer though... For the price of this device you can go on Ali express and buy at least 2 similar devices which heat better and use current tech with the same amount of money

We use our ipad App for star gazing when we set out for a night of star gazing - as we live in the north west our window of discovery is hit or miss. We keep this in our glove department - a) energy bank and b)hand warmer. We recently experienced a power outage and it was great knowing that I had some power bank for my phone. Also brand was important as we have purchased Celestron products and have never been disappointed.

Super Handwarmer - etwas teuer und etwas klobig vielleicht, wird aber sehr schnell warm - aber dabei gerade nicht zu heiss - und hält gefühlt wirklich ewig warm.Auf die Ladefunktionen kam es mir dabei nicht an.