Perfect for puppies or kittens and arthritic pets on those chilly winter nights older pet or those with joint problems that need extra warmth. Now you can provide it for them with this innovative disc. Used and approved by vets and top breeders all over the world. Just place in your microwave for 5 to 7 minutes and you will have a durable long-lasting "hot water bottle". One session in the microwave will provide 12 hours of warmth for your pet. Great for newborns and whelping situations. Microdisc is 9" in diameter. Comes with Snugglesafe Comfort cover. Colors may vary.