All these hats are 100% wool.I have a few and they all shrink after awhile.They have water repelent on them, which does not last forever.I always buy a little larger and put the soft side of velcro in the brim,that way I get a perfect fit.Stetson has a few with 2 1/2 brim, I have been wearing the "expedition", got it on **** $30.They are crushable hats ,and will come back to the original shape for a while.They are different in that other hats are "stiff".The crushable Stetson,s are great shooting hats.2 1/2 brim or less !Also not all smalls or m,large are the same size !