I have had mine for 5 years and love it. Now I buy them for new boarders at the barn for Christmas gifts. I also love the fact you can get several uses out of the hand warmers if you put them in an air tight baggie after use. They last 8 hours and I am usually only out there 3 to 4 hours. Once the bit is in my horse's mouth I put the warmers in my gloves or mittens, some even have zipper compartments for them, to get the full use out of them. Love this product.