Rosewood chillax cool pad large no more over heating perfect for everyday use in the summer months great for dog shows and for dogs prone to overheating perfect for use in pet beds crates kennels or for car travel the chillax pad is activated by weight or pressure no electricity water or refrigeration required the pad will be cooler than the surrounding temperature for up to 3 4 hours of constant use it will automatically re charge itself as your pet moves large size approx dim