I had four of these and my new puppy chewed the zipper off one (guess I forgot to hide it in the zipper flap).
My previous set of dogs have died and the puppy, now 4, inherited them. They are still going strong. Buy at least two per dog so you can wash them and hang them out to dry. Excellent value and one of the few covers that dog hair and dirt doesn't stick to. We like the red ones but had two red and two blue in size large for our GSDs and now our black Labrador. They machine wash really well. I always line dry them and they do take a while so good idea to buy two per dog. They have an inner lining. No idea if they are waterproof, never been an issue, ours is inside. We fill the cover with two, inexpensive Kmart foam mattresses for dogs. Used to be one mattress per dog but have doubled them now since we are down to one pooch. Highly recommend this product.