100% cotton bag filled with an organic rice and flaxseed mixture. Sectioned for even distribution. Can be used: warm from the microwave: for pain relief or cold feet cold from the freezer: for pain relief at room temperature: for relaxation with soothing weight Removable cover is machine washable and lay flat to dry. Measuring 21” x 6” this bag is perfect for neck and shoulder discomfort. Additional covers available for purchase.