I was definitely surprised by how powerful this massager is, considering it's rechargeable and not plug-in. It took me a second to figure out how to put it on, but now that you have my picture, you can skip that step :) The massager's little arms are reasonably powerful. Out of the box, I got about 15-20 minutes on a full charge, which is about what I expected. It probably could have been longer if the heat setting was turned off. Note: when you turn it on, the heat automatically turns on. I learned that the hard way too. Also, if you're wondering if you can use this on other areas (lower back, thighs, etc.), you definitely can. Overall, I'm very pleased with this accessory and will keep it handy. I highly recommend it.