Size: S Quantity: 4 new + 3 used (I'll also include 3 dirty ones, but please discard them if you don't want them) The size is S, but it's a foreign size, so I bought them for medium-sized dogs. They are not disposable; you replace them when they tear. It's quite difficult to put them on by yourself without the proper tools... that's the impression I got. Since these are used items, please refrain from purchasing if you are looking for perfection.