HEAT WAVE Instant Reusable Heat Pack- Medical Grade (8x12) Stiff & Sore Muscles,Pain Relief, Hiking and Camping Warmth Made in USA Large Green 2-Pack

This is not the first time we have bought and we are very satisfied! Very good quality and easy to use. Keeps warm for a long time about 4 hours. Definitely recommend!

EDIT: I had to throw it away today only after using it for three times. It left sand like particles all over my bed sheets. It also doesn’t stay hot for very long. The concept is cool though.I am using this right now. It is awesome. So easy to use. It’s a little on the hot side for me so I wrapped it up in a shirt. I am very happy I purchased it! Works great!

These are perfect for having instant heat where you need it. They are especially easy to use if you have a water vessel to renew them on your wood stove. The click coins inside work easily and the material for enclosing the liquid is of thicker mil than other packs that were even pricier. Go USA!

This is a very useful and very neat product! It works exactly as described -- click the metal disc, and the clear liquid instantly starts turning into a crystal-like product and produces nice heat for a good hour. Boil it until it's clear again, and it's ready for another round. Ingenious! Since the outside of it is ordinary plastic, I would recommend you wrap it in a towel before boiling it, to avoid having the plastic touch the sides or bottom of the pot. Otherwise, the plastic could melt. I've also found that, after boiling it, the pack stays warm for a while, so you can actually use it again when it's fresh out of the boiling water, while it's still warm -- it stays warm for a good long while. Then, once it cools, if you're ready for more, it's ready to be re-activated. Pretty neat! I'm considering buying more of these in different sizes. Excellent product -- I will be using it a lot.

I bought these for camping. We camp in the Rockie Mountains from early spring throughout late fall and with Colorado weather being fickle, we've been snowed on multiple times. I am always freezing, I'm often unable to heat my sleeping bag because my wonderful body just doesn't produce warmth. So, I bought a heat wave pack, crack it and drop it into the bottom of my bag & it keeps me warm for at least two hours if not longer. By the time it cools I've created enough heat in the bag to keep me warm through the night.Update - 03.16.17 - I was resetting the packs as a I normally do, in a pot of boiling water and both set of seams burst and destroyed the heat pads. They were only in the water for 7 mins and I had reset them this method 20 times before. Super disappointed. I will buy to more because I need them for camping but maybe not from the same company. The smaller version I have from a different company has lasted me two years with no issue so I wonder if these two had a manufacture defect.

I bought this product after having purchased a similar and smaller heart-shaped product which I love. This is a large size which I need to fold in half and put into a large pot to restore it before the next use. I have used this product about 6 times so far with no problems at all. I do worry slightly that the product must be folded in order to insert it into a large pot. The vinyl case seems to stretch and has not torn; but I worry that repeated stretching might eventually cause a leak. The small disk which floats inside is much more difficult to activate the chemical reaction which causes the heat. I think this is a good feature rather than a bad one. My other heat pack (small heart shape) has a metal disk which does not have the supporting plastic like this one. I would say that this one is better because there is much less chance to activate this one due to accidentally bending the disk. Overall, this has been a great product so far even though I do worry about bending it to boil it. I never worry about the vinyl case of this one or my smaller one melting in the pot due to the boiling water. I typically use these to heat my bed in the wintertime. I would say the heat lasts at least 2 hours, so it works great to keep me warm and I am always sleeping by the time it cools down at which time I don't need it any more. The time to boil and recover this is shorter than stated - about 20 minutes.

I am assuming this works for the purpose it was intended. I dont have aches and pains; I was buying this to see how a store-bought one would work before I tried making my own. My intended purpose is to keep pipes from freezing- according to reviews the heat was supposed to last for hours. It does not- not even including the required boiling first. So back to the drawing board. This product arrived solid. The excuse given by the company was "difficult handing" but that's not true- after using I boiled it for storage, and noticed the next day it was rock hard again. I gave it 5 stars because it functions, I have a fascination for non-electric things, and it seems well-made. But if one had pain, they'd have to go to the trouble of getting out a big boiling vessel, boiling it, and then activating it. Seems a hot water bottle would be a cheaper alternative.

Great product, does exactly what is says. It take a bit of dedication to heat it ahead of time for future use so it gets less use than my bean bag, but it delivers nice even heat to a large area at the same temperature for more than 20 minutes.

These heat packs are a little expensive but are definitely worth it. I have been using 1 in my wetsuit and it’s so warm. I would recommend putting them in a sleeve or something because the corners are a little sharp so may end up with a friction rash depending on how much it moves around.Also great for lower back pain! Stays warm for ages.Reheating is a bit annoying as they are quite large and don’t fold up until they have warmed up a bit. Need a big pan or deep ish pot.

First time use out of box : amazing!Followed instructions to re use : does not work. Just stays in solid form. Tried different methods. No use.Also bought the mini versions : same fail.

The almost instantaneous heat of this product is wonderful. The heat is quite long lasting if wrapped in a towel. It would be wonderful if you did not need to boil the pack after use. Hopefully that technology may appear soon.

got it and it works thanks.