ThermalSoft Gel packs are double-duty packs filled with a non-toxic silicate gel. Heat them in the microwave for heat therapy. For cold therapy, put them in the freezer. The large gel pieces mold to the contours of your body to deliver soothing heat or cold therapy. Two thin layers of vinyl make these packs sturdy yet comfortable to the body. Will not crack, leak or become brittle with repeated use. Provides up to 30 minutes cold therapy treatment. Standard Size - 11" x 14"