Hot to Go Reusable Heat Packs - Buy 4 Get 4 Free!

I purchased these to help maintain heat in my wetsuit for cold water scuba diving. We have some rechargeable warmers we use when we're camping, hiking, or whatever, but I needed something that could be submerged. When I tried them out, I was worried that the heat would be too intense. It was plenty warm, but not unbearable, and very nice after I was at depth for a few minutes. I'm glad they came in an eight pack so I can do repetitive dives when it's inconvenient to boil water between dives to reset them. When I'm doing longer dives, I can place extras in my wetsuit and activate another one when the first one starts to fade. The round ones fit really well on top of my toes without making my feet feel squished. I left them out in my toolbox in subzero temperatures overnight and they didn't leak or activate.

If you spend any amount of time outdoors, while it is cold out, I definitely recommend buying a few of these. The best part is that you can boil them and reset them with a lot of reusability

Hey amazon so I just had to write a review for these stupid little things! Let's start with I didn't expect them to last or be good at all because of all the negative reviews. So I dropped $20 and gave it a shot. Well here I am on amazon again writing a review for these heat packs 2 years later. They all still work perfectly, I have the full set still and none of busted or broke or stopped working like everyone says they do. I absolutely love them. I think the only issue I have is that the heat doesn't last long, it never did. It lasts maybe half an hour at the most before they're back to room temperature, and need to be boiled again to reset. But otherwise they are an amazing product and they do seriously last a long a** time if you take care of them. They're the perfect sustainable replacement to disposable hot hands, and they really do save money after using them a few times. Definitely not going back after these finally give out lol

UPDATED 11.12.24 - Once you figure out how to activate them, they work perfectly. Reactivating is MUCH easier than the 1st activation. TIP: Bend the metal disc backwards - they are slightly concave, so bend in the opposite direction - I read this on someone else's review when I was unhappy and it totally worked.I have wrecked 2 of the 8 by using a hammer to hit the small metal disc for activation....cannot get them activated in any other manner. Unfortunately, this causes them to split at the seams and the company says to not boil them if they leak. The other 6 I have not taken a hammer to YET!!! Once activated they do provide nice heat....if you can activate them - key issue! TOTAL WASTE OF MONEY!!!!

Bought my first batch of them 7 years ago! The last one is still holding steady. For my needs they stay hot enough and I would say, on tender skin, they almost get too hot! Easy fix to wrap in a paper towel. Besides health needs I also use them for transporting baby chicks! Came back to buy another set!

I have been on the lookout for the best type of hand warmers for three different situations: (1) for emergency preparedness, (2) for kids' hands while biking year-round on the cargo bike (they get quite cold because they're stationary behind me as we ride through the wind), and (3) for the school aged kids as they walk to school and at recess. I considered disposable hand warmers (but don't like the waste), electronic hand warmers (looked too expensive to start with), and these. I was especially drawn to the low price point + the fact that these are reusable.As we've used them the last six months, however, my biggest complaint is that their heat simply doesn't last long. They only have 10-15 minutes of good heat and then they become bulky rocks in the kids' pockets. This makes these nearly worthless for emergency situations. I started keeping them in my pannier for cold hands while biking, but I have now found 3 that got punctured and then crystalized all over the inside of my bag (ugh). I also keep finding them hard in the bottom of the bag, having gotten activated from the bumping while we were riding. Together, that makes them less than ideal for bicycling purposes. That leaves me sending these with the kids on their way to school. Because it is a short walk, this has been by far their best application. The kids take two apiece: one to enjoy on the way to school, and one to crack open at recess time. They're very pleased with this, and share with gloveless friends on cold days.Even the school application has its issues, however. The biggest problem is that these are fairly cumbersome to "recharge". It takes about 10 minutes of boiling to get them reset, which we do when the kids come home from school, but then I have a sopping wet rag every single day (because of the boiling instructions I found on YouTube) that needs to be dealt with. That means it's roughly the same amount of boiling time as actual use time, which feels slightly absurd. In order to not waste water, I let the water cool and then use it on my house plants-- but that's a lot of water when we're using them every day! In an emergency scenario, finding that much water to boil and having a fire to boil it sounds like a lot of requirements for a mere 10-15 minutes of hand heat.Would I give these another chance? I don't honestly know, but only for the school application if I did. I will next try buying an electronic hand warmer (and then eventually buy one per family member if the first one tests well). Even if the electronic ones work out, I may still continue using these reusable ones for school because they are so much less expensive-- and therefore I am much less worried about these getting lost, stolen, or broken in the school context. For emergency preparedness, I have thus far purchased a large stock of the disposable ones for our 72-hour kits and our car emergency kits because at least I know those work very reliably, even if they unfortunately get trashed afterwards. The electronic ones may replace those, so long as I keep them well charged during normal times, and perhaps I would keep a couple of the electronic ones on my bike.In all, the search continues. These are inexpensive and definitely work in limited scenarios, but they're also short-lived heat and a lot of work to maintain.

I have been using these for months and I couldn’t tell you the science behind it but I throughly enjoy how I have been able to use them for just about anything. The heat lasts for at least 30 minutes and it could be up to an hour. I enjoyed getting the 8 pack because I don’t need to boil them as often. The quality is amazing.

These are perfect for my use... I mostly use them in my pockets to keep my hands warm while I walk my dog or wait in outdoor lines. Gets nice & warm... but only stays warm about 20min or so. And to carry more, for more lengthy needs, can get heavy & crowdedin my pockets.I have about 10 for the 2 of us. I'll order me once these stop working...But I've had them about a year & they keep resetting (you have to boil them to melt the crystals that form. )