The CO Skulls fit very differently and I suggest you to to a retail store and have a knowledgeable person (whether it be an employee or a horse friend you bring) help you fit it.
Skull caps, esp the Charles Owens have to fit really snugly at first because the cushioning will compact.
The first skull cap I got was a CO skull and I got it to fit like my first plastic helmet. A few weeks later it was so loose it would flop over my eyes when I jumped and I had to get a new one. ..and then there are all the other Skull caps I've dented, cracked and smashed by falling on my head!
I have a head that is on the large side (22"), but my real challenge in the hat and helmet fitting area has been my head shape. It is narrow from front to back, so most hats and helmets are too small front to back, with too much space from side to side. The Charles Wilson Pro fits me perfectly.... I actually forget that I have anything on. I've tried other Charles Wilson helmets, and, yes, they all have a different fit. Good luck!
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