My cat wore it only a few times but preferred wearing smaller collars. Fits smaller kittens (or other smaller animals) best. ***Please see second photo for sizing measurements*** Made for convenience and function, the vest design makes this harness easy to get on and off. And the adjustable strap creates a Perfect Fit for your kitty with some room of growth. (Tips: Please give your cat some time to get familiar with this harness for the first time use) Questions? Feel free to leave a comment below!