I purchased these men's shorts by #1613 originally for my son who wears a men's medium in US sizes. Coming from China I figured they'd run small, but had no idea it would run this small. I had my 9 1/2 year old grandson try them in as he wears a size small in men's. He's a tall and solid kid, not fat just chunky. They fit him perfectly, so at least they didn't go to waste or need to be returned. They washed well and are made very well with a nice quality drawstring. Nice pockets and he loves them. That said if you're looking to buy these I'd recommend going 2 perhaps as many as 3 sizes up to ensure a good fit ..