Reusable heat pack
Reusable portable warmly heat pack, which requires no artificial heat source, in different shapes for hand, shoulder, back and foot. Do not need to put into the microwave oven; it’s much more convenient than gel pack. Just fold the metal sheet inside the heat pack and then it will start crystallization. When the crystallization is completed, it’s ready to use. To recharge, place the heat pack in boiling water with cloth. Heat it for 10 minutes until the crystal is dissolved. The heat pack can be used for providing warm and releasing pain with shape of shoulder/knee/back.