It's a free size. I bought it last year and wore it when I weighed about 42 kg. It fits without being too loose. It has a zipper and hook in the back, so it's secure. There's a belt in the front. I've only worn it about twice. My parents bought it for me, but I didn't wear it much, so I'd be happy if you bought it. I'll use a lint roller to make sure it's clean before shipping.