My hands get extremely cold very quickly even though the rest of me is fine. I have spent a small fortune on different hand warmers, trying them all out for myself as you can't trust the information that comes with the product.
If your hands get cold then read on!
I first tried the zippo hand warmers (left of picture) zippo hand warmer review - Google Search - https://www.google.com/search?q=zippo+hand+warmer+review&oq=zippo+hand&aqs=chrome.2.0j69i57j0l6.4704j0j8&sourceid=chrome&ie=UTF-8,
When they work they work for a long time (approx 6 hours)and get to a good temperature. However, they are very unreliable, sometimes they don't light at all and sometimes they go out very quickly. I have tried all the advice on line to keep them going, it did not work. I would not recommend them at all as they will let you down when you most need them.
I used the charcoal hand warmer as well (middle of picture) Charcoal Handwarmers - https://www.outdoorgear.co.uk/Strider-Charcoal-Handwarmer-Case-sku36901601.asp
I used the charcoal hand warmer for a couple of years. It worked 9 times out of 10 as opposed to 6 times out of 10 for the zippo, but that still means 1 in every 10 days of use they let you down leaving your hands cold.
They lasted for around 6 hours and the heat was no where near as good as the zippo, better than nothing though. I could create more heat by lighting both ends of the charcoal stick but this halved the life span of the heat. I now use it as a spare and use the electric one regularly (see below).
The hot rox electric hand warmer is the one I now use (right of picture) Hot Rox Electronic Hand Warmer - Double Sided Heat With Power Bank - https://www.uttings.co.uk/p130821-hot-rox-electronic-hand-warmer-double-sided-heat-with-power-bank-hrds1/?option_id=117107&adwords=true&gclid=CjwKCAiAxMLvBRBNEiwAKhr-nIv465BB3lw5w6ja52huTv9wLKGGTm8lOU8QzGpmYI1-nXD02AntARoCtM0QAvD_BwE
It takes perhaps 2 hours to recharge. It lasts for around 3 hours on high temp and perhaps 4-5 hours on medium temp. Medium temp is just about OK but you really want to use high temp. They work every time! I would recommend this hand warmer. It's important not to get this 'newer model' hot rox mixed up with the older model which is still widely sold. The older model only warms up on one side and is more of an oval shape. The newer model fits in your hand far better and warms up both sides. I have bought 2, one for each pocket! Plus it can be used as a power bank although I have not tried this yet.
Hope this keeps your hands warm over winter
If your hands get cold then read on!
I first tried the zippo hand warmers (left of picture) zippo hand warmer review - Google Search - https://www.google.com/search?q=zippo+hand+warmer+review&oq=zippo+hand&aqs=chrome.2.0j69i57j0l6.4704j0j8&sourceid=chrome&ie=UTF-8,
When they work they work for a long time (approx 6 hours)and get to a good temperature. However, they are very unreliable, sometimes they don't light at all and sometimes they go out very quickly. I have tried all the advice on line to keep them going, it did not work. I would not recommend them at all as they will let you down when you most need them.
I used the charcoal hand warmer as well (middle of picture) Charcoal Handwarmers - https://www.outdoorgear.co.uk/Strider-Charcoal-Handwarmer-Case-sku36901601.asp
I used the charcoal hand warmer for a couple of years. It worked 9 times out of 10 as opposed to 6 times out of 10 for the zippo, but that still means 1 in every 10 days of use they let you down leaving your hands cold.
They lasted for around 6 hours and the heat was no where near as good as the zippo, better than nothing though. I could create more heat by lighting both ends of the charcoal stick but this halved the life span of the heat. I now use it as a spare and use the electric one regularly (see below).
The hot rox electric hand warmer is the one I now use (right of picture) Hot Rox Electronic Hand Warmer - Double Sided Heat With Power Bank - https://www.uttings.co.uk/p130821-hot-rox-electronic-hand-warmer-double-sided-heat-with-power-bank-hrds1/?option_id=117107&adwords=true&gclid=CjwKCAiAxMLvBRBNEiwAKhr-nIv465BB3lw5w6ja52huTv9wLKGGTm8lOU8QzGpmYI1-nXD02AntARoCtM0QAvD_BwE
It takes perhaps 2 hours to recharge. It lasts for around 3 hours on high temp and perhaps 4-5 hours on medium temp. Medium temp is just about OK but you really want to use high temp. They work every time! I would recommend this hand warmer. It's important not to get this 'newer model' hot rox mixed up with the older model which is still widely sold. The older model only warms up on one side and is more of an oval shape. The newer model fits in your hand far better and warms up both sides. I have bought 2, one for each pocket! Plus it can be used as a power bank although I have not tried this yet.
Hope this keeps your hands warm over winter