To complement the innovative design of the Freeze Sleeve and provide relief to areas like the back, hips and shoulders, we've created the Flat Pak. Sized at 12" by 17", this sleek black pack can cover large muscle groups in various parts of the body. This therapeutic cold/heat pack helps speed relief and recovery by efficiently treating sore muscles and joints. The specially formulated gel is super soft and flexible. It is also safe to use in conjunction with other treatment products, including compressed air massagers and muscle stimulators. Simply place the Flat Pak on areas of discomfort after heating it up or cooling it down in the freezer for either hot or cold therapy. Supplying up to 20 minutes of doctor-recommended cold/heat therapy without the risk of burns or damage to the skin. Reduce swelling and relieve aching muscles and joints with this revolutionary take on the cold/hot pack.