Our son, has a short wetsuit that he has worn for a year or so now that is a size 8. We sized up and got this in a size 10. He is not a big kid at all, 10 years old and is 60lbs - 4'4. He could not get this thing on. He was bound and determined he wanted to try and almost couldn't get him out of it. He only got it halfway on. The arms are very slim and tight. Even if he got this on, once it got wet, there would be no way he was getting out of it! However, it was good quality material and would rSee full review