Made in USA: HEAT WAVE Instant Reusable Heat Packs – Large (8x12”), Reusable Heat Pack for Muscle Aches, Back Pain, Pain Relief, Click Heat - Premium Medical Grade

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.

This is the second time to purchase it and it isnt working this timeee !!!

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.

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.