S4U Reusable Instant Hand Warmer Heat Pack Hot Gel Handwarmer Pack Click for Instant Warm Heat Anytime Perfect for Pockets Travel Camping Hiking Outdoor Activities

Bought a 2 pack of these. The first one failed on its 2nd or 3rd use and started leaking. The problem being that the welded seal around the perimeter was much too narrow, and it separated open. The 2nd one lasted a few more recharges, but then developed some imperfections inside meaning that it was impossible to properly recharge - no matter how long you boil it for, it never went completely clear, and thus re-crystallised on cooling.Nice idea, but poorly made, so waste of money.

Good service from the vendor, no problems with the packaging or label.Item does exactly what you would expect, and produces enough heat to keep me happy on my Winter hiking trips.On testing, I found a good heat for about 14 minutes, gradually tapering off to ambient surrounding temperature at about 29 minutes. Recharging is as stated in the description. I first bought a small pot of water to the boil ( in this case 1.5 cups of water in a 10 cm Zebra Billy Can ) with a small handkerchief in the bottom of the pot ( to protect the hand warmer from the heat of the base ) removed the heat source and put the hand warmer in. Took 5 minutes and 44 seconds to return to the liquid state so that all of the crystals had melted and I wasn't running the risk of the pack still having solid crystals in it and restarting the chemical reaction when I took the pack out of the water.Meets my needs and is used regularly.

Bought as a gift for someone with very cold hand and they love them! They're easy to use and great that they're reusable, although it does take quite a long time to fully recharge in the boiling water. They have been recharged several times already with no sign of degrading, however, it is expected that they would become slightly less effective over time, hopefully not for a long time yet though!

Slightly larger than I expected, doesn't stay warm very long, thought there was going to be two in pack but there's only one (my fault no doubt for not reading description carefully enough) - seems a bit pointless really - what with the amount of time it takes to boil and reactivate it for the length of heating you get I can't really be bothered to use it. Can't understand why they can't make one that you can microwave since most microwaves take small bits of metal so long as they are not touching the sides.

This is a good product, however it isn't great.I purchased this product to help with a medical condition I have, however it simply takes far too much effort to continuously reset the hand warmer. If you would only use this occasionally then it will likely be of use to you, if you are planning to use it often say multiple times in the day then you may find it a bother to reset.The product is a nice size, it is pretty well made and generates some good heat also.The real negative for me, which gives it 4 stars really is the fact that it can so easily "activate" on it's own and then you have lost all the heat and you will have to reset the pad.  Magic Gel Reusable Hand Warmer Heat Pack

This is a single hand warmer (some are sold in pairs) and works by clicking the little metal button in the liquid which then causes a reaction which generates heat - and it works. Inside a glove, it seemed to work for half an hour or so and was pleasantly warm - which is pretty much what you want. Not unbearably hot, nor too cool. As it works, the liquid solidifies and then has to be 'recharged' by boiling it in water until all the crystals have dissolved. This last bit is important, and this is made clear on the instructions, which, to be frank are a bit patronising but at least they do make it absolutely, abundantly clear what you have to do!At about £3.50 or so, its not expensive and is useful for those chilly mornings when its only the fact that the dog needs to be walked that makes you turn out at all! Its been used several times so far, but I can't comment on its longevity, other than to say its still going strong ta the moment.

Activated, wrapped in foil and then used a calibrated thermocouple to measure temperature over time. It took 2 minutes to get up to 42 degrees C, stayed at this temperature for 5 minutes then over the course of 25 minutes steadily dropped to below 35. Definitely not the 57 Degrees C advertised but one in each pocket will just about take the edge off on a cold day.

Don't know about pain relief as I don't suffer from this but I do dislike the winter playing golf because of cold hands. So having these in my pockets help a lot. I use them one at a time and they last the whole round, just keep my hand warm enough to grip the club. So very grateful for this invention and pleased with this purchase.