This appears to be made well from quality materials. However it weighs a lot. With arthritis it's too heavy to continuously hold for more than a minute. When I placed the order, I imagined it would feel like holding a warm cup of coffee. It doesn't get that warm & when you put it in a cold hand, it doesn't stay warm. You have to keep turning it over to the other side & let the 1st side warm up again. In just a few minutes the power goes from 100% to 80%. I haven't used it as a charger yet, & won't because it's too heavy to carry in my pocket or purse. I'm very disappointed in this product. I'm giving it away to someone stronger & with warmer hands than mine.