At the top of our list, we find MagTwins, the rechargeable hand warmer from Warmly that stands out as the best product. This sleek unit maintains heat for up to 10 hours and has a battery that can be fully charged in just three hours. Once activated, it only takes 10 seconds for it to heat up and be ready to be placed in your glove or pocket.
Warmly has included a clever extra feature in MagTwins that allows it to be used as a power bank when needed. You can easily connect other devices to it via a USB cable. The same connection is then used to charge up the hand warmer itself. During charging, this is clearly indicated by LED diodes.