As most of the other reviews state, this hat has a pretty small circumference.  The model in the picture is misleading - it won't sit as far down on your head as it does in the picture.  I think that I have a pretty small head for an adult female and it barely fits.  However, good news for kids: it has a velco adjustable strap inside to make it smaller (not like any adults will need this feature).  Too bad it's marketed as "McGonagall's hat" who is a mature adult, where this would be more accurately marketed as a "Hogwarts 1st Year Student Hat" - ha!

However, I am happy with the look for the price.  It has wiring around the hat brim that takes some time to bend to look just right, but it's very customizable.  Happy with my purchase overall (but only because my head is small).