All Caldera reusable Therapy Gel is Made in the USA and can be applied either hot or cold. Therapy Gel remains pliable when frozen, is latex free, non-toxic, and microwave and freezer safe. Sold as single unit Size: 4.5 x 10.5 Pliable when frozen Latex free Non-toxic Microwave and freezer safe Economical--use over and over. Used by physicians, trainers and athletes. Sore Muscles, Aching Joints Sprains and Strains Insect Bites Sinus Pressure, Migraine Dental Pain Hot Flashes Menstrual Cramps