Hand Warmers Rechargeable 2 Pack, 14000mAh Electric Hand Warmers Reusable, 20Hrs Warmth Double-Sided Heat Up to 55℃, Portable Hand Heater for Raynauds, Hunting, Golf, Camping

What can I say, these are a good send.Designed to keep your hands warm and that is exactly what they do.The battery is surprisingly good and lasts.Depending on what settings you have them on the do last 8+hours.I put these in my pocket on L1 or H1 when I gets t to work and they are still going with around 10% battery when I leave.They also can in very handy to charge smart phones when we had a power cut but will only last one full charge.I'd also say you could use these for other things like shoe warmers and maybe even alternative to hot water bottlea but probably not as comfortable.Pros:Get very hotLast long on lower settingsDouble as power banksDual usb C charger cableDigital battery percentage displayEasy to use one you work it outCons:Not very ergonomic to holdPoor instructions

Upon receiving these handwarmers I charged them up to 100%. The next morning they were still at 100% and I decided to test them to see if the manufacturers stated claims for these handwarmers was the usual manufacturers BS, or if they were being honest with their claims.The claims I was interested in and thus tested, were for single side heating L1: temperature of 38° to 42°C; run time of 20Hrs (2 x 10Hrs); and charging time from 0% to 100% of 4 hours.To say I was pleased with the results of my test would be a vast understatement! They were:- L1 temperature average during test was 40.5° to 43.5°C and was consistent throughout the test [tested with both an infrared thermometer and a thermocouple attached to my multimeter].- Both handwarmers ran for exactly 12Hrs, thus giving a total of 24Hrs.- Charging from 0% to 100% for both with supplied double charging lead 3hrs 45mins.In summary:Slightly warmer than claim, ran 4 hours longer than claim, and recharged slightly quicker than claim. See attached charts for details.So yes, I most certainly can highly recommend these handwarmers to you.

I have to say that I wasn't expecting much from these, the Boiros 4-in-one rechargeable hand warmers, not least because the packaging was Chinese-generic and Boiros name was implemented in a couple of cheap stickers. However, the actual product is well made and works rather splendidly. Not least because of the potential for being tiny emergency power banks as well.Note that in all the photos here, the refresh rate of the LCD displays is too slow for the camera shutter speed, so not all segments are shown in the images. But they're fine to the eye!The units are charged (both at once via a single 'Y' cable, unusually) by USB Type C at 10W and a full charge takes 90 minutes or so from any Type C source you happen to have around. Output, if you want to use them as power banks, is via USB-A and also at 10W. But that's OK for emergency use, I suspect, especially with this lowest common denominator port.The idea with these warmers is to use a couple of meaty power bank-grade Li-Ion cells to discharge through one or two heating elements per 'hand', giving a genuine full day of use, surprisingly. As a physicist, I'd have guessed that generating heat would deplete the small cells rather quickly, but it seems as if this isn't the case.Giving, again, a surprising amount of flexibility, are 8 different heating settings per unit. So 4 settings for two heating elements, one in the front of each unit, one in the back. These correspond to target temperatures in Centigrade, so ('High' being double sided, 'Low' being single sided):H1/L1:38-42°CH2/L2:43-46°CH3/L3:47-50°CH4/L4:51-55°CIn practice, if you're going to grip these things 'bare', then the '3' settings are just too hot for comfort, but I think '3' and '4' might be more for inserting inside something else or an item of clothing. I did some benchmarking tests against the marketing claims (e.g. 12 hours for L2) and found that the warmers matched the numbers across the board. So yes, L2 (level 2, single sided) heat lasted for over 12 hours straight. Obviously, if you fire up both heating elements at level 2 then you're looking at six hours continuous output.Setting the heat level, firing up the torch (not very bright, but OK for finding keys or a lock or similar), or just seeing the current battery status, are all done through multiple and long presses of the two buttons on each unit, as shown, and it's all explained well in the paper instruction manual.Before passing judgement on the warming functions, I wanted to comment on the power bank aspect. Although probably best left for emergency use because of the 10W output limit (per unit), having 7000mAh on tap in such a small pocket-friendly gadget is worth noting. Or 14000mAh if you have both units with you. That's enough to recharge several smartphones, even if not at lightning speed. They'll get you home, etc.These hand warmers do - absolutely - work as advertised, but their worth depends on the use case. Because if your fingers are wrapped around a warmer unit then you can't do much else with that hand. The ideal use case is standing around in the freezing cold watching a kid's football game, that sort of thing, where you're having to be in a cold environment and just trying to keep your hands from going numb.An intermediate use case would be, for example in my case, walking the dog in winter, where one hand is having to hold the lead and the other potentially either (temporarily) holding used poo bags or taking a phone call. Juggling hand warmers here would be more trouble than it's worth and (simply) good gloves would be better.The marketing material shows skiers and hikers, but wouldn't those activities involve holding poles of some kind?So the actual effectiveness of pill-shaped hand warmers depends very much on why you want them - and we're all different. What I can say is that these work as advertised, are very well made (albeit in plastic), and have decent emergency power bank and flashlight functions. I see some negative reviews on Amazon, but my experience has been all positive.I bought these at £32, which seems a good price, but like most Chinese-made products from brands you haven't heard of, prices do fluctuate, so your mileage may vary here.

These things are great. They can both be charged from a single usb socket. Each one, has 6 heating modes. So far, I've only used the L1 and H1 settings, which are the lowest modes for single and double sided heating. The battery lasts for ages and gives out plenty of warmth, and the best part is that there's two more settings on single and double sided that I've not needed to use. It's also handy as a USB power bank, if the need arose, but this isn't what I purchased them for.The display is clear, shows the amount of power clearly, as well as which setting you have selected when turning on the heater. Having a torch mode too, is a plus, but again I don't tend to use it. It's nice to have though just in case.update: These are so good, I ended up getting a second pair as I mislaid the first. However, the first pair turned up, so I've decided to keep them in my car, just in case I get caught out without them. I have been using them now for a couple of years, and frankley, they're the best warmers that I've used.

Highly recommended. Heated both sides in comparison to other similar devices and has many different settings to satisfy your needs. Fast charging and battery lasts long. Small and light to carry easily.