has been a favorite for years. It can also be used as a cold back by putting it in a plastic bag in the freezer for a few hours or over night. It is filled with organic rice and is sometimes scented. Most have a strap at either end so you can hold it in position or able to apply pressure by pulling on the straps. Some styles have a Velcro strip to help secure it in different locations.
It only takes 2-3 minutes in the microwave to heat up. The heat will last for about one-half hour.