very usefull. i used to use this almost every day, either on my back or neck. after a while from heating it up so much it would start to smell like burning and after a while exploded. makes sence cause i did use it a lot!

This item is so handy! Although it is marketed as neck and upper back you can use it on your mid-lower back, knees and anywhere else you need relief. It holds the heat well and lasts for quite a while, almost 30 minutes. I've also found it useful as a premassage tool, it really helps to loosen up tight muscles. I haven't used it cold yet but I'm sure that work just as well!