HypaCool Instant Cold Pack, Compact, 12.5 x 15cm (Pack of 24)

I wanted to have a filled out first aid kit, just for the sake of being prepared, and so I wanted to get some ice packs that didn't require freezing, not to mention it'll be really nice in summer to just be able to pop one and have a cold pack.I would recommend when you try to "pop" the inner pack, don't use your finger tips, put it between the palm of your hands and press, you can put more pressure than you think to pop the inner pack and I've run over one of these with a chair wheel on accident and the outer packaging still didn't burst so that's a major plus.So far I've used these for a swollen knee, tooth ache (just holding it over my cheek) and to help numb the itching in an area and it worked perfectly for all these situations.How long it stays cool seems to vary on where you place it, if the area is already warm, and what you wrap it in but in all cases it lasts at minimum of 20 minutes which seems ideal.I'll definitely be buying more of these when I run out.

I bought these for warming up my sleeping bag before bed time when I cannot use a hot water bottle. They get hot, but not as hot as the handwarmers and they don't hold the heat more than 30 minutes. Just as expected and perfectly adequate for what I want them for.And a plus compared to handwarmers is that these do not need oxygen to work and they reach top temperature within seconds.The minus are the misleading user instructions. I could not get the inner bag to burst and release the reactant liquid just by squeezing it. I had to lay it on the table and punch it. Mind you, I didn't punch it hard and recommend to do it only on a wipe-clean surface in case it bursts completely and splashes all over the place. Once I figured out how to activate them they are an excellent product. Also unlike some others brands, as they are hard to activate they are unlikely to do so when you don't want them to.

Completely useless. I ordered 4 of these and when they arrived I thought I'd try one out to see A) how they work so I know what to do when if I need them and B) how effective they are... they aren't.Actually, that's a bit unfair because truthfully I have no idea how effective they are because, due the the pack's poor designs, I don't know if I even got them to work.These aren't like the old 'snap pack' hand-warmers you used to get which were solid and easy to snap and activate; these ice packs are more like bean bags with a pouch hidden inside.You are meant to shake the contents to the bottom, locate the inner pouch and squeeze it to burst/activate the packet and then mix the contents up with a shake.The problems are twofold. Firstly, it is near impossible to locate the inner pouch because you can't see it or feel it. Secondly when you do eventually locate it (or locate what you think might be the inner pouch) you can't squeeze it to activate it hard enough because the the ice pack is so full of air you're scared it's going to explode under pressure showering you in a toxic goo.I have no idea if the pack arrived activated and spent. If it arrived OK but I failed to activate it properly, or if it worked fine but was just rubbish and didn't work at all. After 15 minutes of squeezing this thing in all manner of ways I failed to feel any change in temperature. Complete waste of money and a poorly designed item.EDIT:OK - after contacting the seller I had another go at this. I was told to squeeze the pack really hard. I mean really, really hard and so I did. Eventually the inner bag did burst with a satisfying gush of cold liquid and the ice pack instantly started working. However, it didn't stay cold for long.You'll be lucky to get 5 minutes of ice cold temperature out of these things and the force needed to burst the inner bag was considerable. Once you've done it once it will be easier to do but the lack of longevity in the temperature means that I can't give this item any more than 2 stars... still that's double what I had previously given it. They work. Just not that for very long.

These definitely got cold, which is a good thing, but completely useless when the packs have holes in them so the liquid drips out. I don’t know if this liquid is sensitive to skin yet but I’ll find out soon as I put one on my neck and now I’m covered in it.

I’m used to another brand but thought I’d try something new. These are small and don’t last as long however you get a lot more packs for your money so it balances out in my opinion. These are perfect for handwarmers but I mostly use them to ease my bad knee and they really help. I would recommend these overall because if they’re tough to activate you’re able to stand on them to get them going and you can use more to compensate for less heat and size. Thanks for reading.