The same Air Activated Heating products that protect industrial safety workers, construction workers, emergency service personnel, military personnel, outdoor recreations, athletics personnel, and equine from the discomfort of the cold is now made for your pet. Includes 20+ Hour Heat Pax Warmer. Comes in Black. Specially designed fleece garments feature built-in pockets that hold Air Activated Warmers and deliver steady heat. Material:100% Polyester Barrier Fleece Wind, Rain, Snow Repellent. Includes 20+ Hour Heat Pax Warmer. Comes in Black. Air Activated Heating Technology Key Benefits: Can be used to combat the cold or for therapeutic purposes(aging pet)etc.; Natural heat generating ingredients stored in soft, flexible inserts. Warmers deliver up to 20 hours of controlled, comfortable, 135 degrees F (57 degrees C) heat. Heating can be suspended at any time by resealing the inserts in an airtight container or plastic bag. Replacement Heat Packs available. Easy to Use: Open the HEAT PAX Warmer wrappers. Insert the Warmers in our garment pockets. Wait 10 minutes for the Warmers to heat up fully. Soothing and comfortable 135 degrees F (57 degrees C) warmth for up to 20 hours. MAT SIZING:   Large  approx 95 lb, 23in x 36ins,  back measurement 21-24 in, includes 4 Heat Pax;