Then I came across Heatka which possibly the BEST solution when it comes to keeping your hand (even up to your forearm) and workspace warm.

And because it takes lighter fluid and lasts an entire day on a single fill, it’s not ideal for on-demand use because you can’t turn it off and on at will. Despite having a battery smaller than the Enduro (7,800 mAh), the FireCel+ (5,200 mAh) was still slower at recharging, averaging 6 hours, 20 minutes (roughly two hours longer than the Enduro). One model we tested heated quickly during the first test, but took three times as long on subsequent charges.

Keep your hands from feeling like freezing while you’re on the computer by using this desktop hand warmer. HotHands is claimed to get up to 135 °F, but it didn’t come close to that temperature in our tests, reaching just 112 °F. They’re similar in size and shape to a rechargeable, and have run times three or four times as long—but like other chemical hand warmers you can’t turn them off on demand. An obsessive fascination with computer technology blossomed from hobby into career before hopping over to France for 10 years, where he started work for New Atlas in 2009.

After 120 hours testing 23 hand warmers over four years, we think the Celestron Elements FireCel+ is the electronic hand warmer you should get. But do that at your own risk; the Zippo manual (PDF) states “once ignited there is no safe way to stop the heating action. The idea was that they will keep her hands warm throughout winter whilst also feeling as though my Grandad is there with her.If you need to keep your hands free while working outside, or you need a hand warmer for occasional use—like when you misplace your gloves or travel to frigid climates for the holidays—the HotHands disposable hand warmer is for you. Others ran slightly longer and hotter on their first uses than on later runs—but performance consistency increased the more we used them. I saw the heatka hand warmer through an instagram advert and wasn’t sure if it would just be another gimmick but saw the money back guarantee and decided it was worth a try. Once the reaction has been ignited there’s no way to stop it, so you have to let the reaction fizzle out on its own.