The ThermoCool multi-purpose dog mats by ambient lounge® are designed to keep your dog feeling cool & comfortable on any surface. Use the large mat under the cover of your ambient lounge luxury dog bed to keep your dog's sleeping temperature even and insulated. (Fits both the large size and fold to fit for the medium) Works after freezing in pet beds - but also stays cool for hours without the need for refrigeration, making it the perfect cooling mat for car seat, patio or balcony or hard surface floor.