i have a hat stretcher (cheap device also avail. on ebay) that I used to stretch cotton hats a size or even two. they’re really neat, because when you wash a cotton hat they often come downa size. I bet you could easily make that one on ebay a med or even almosta large with a cheap hat stretcher. a stretcher is basically two shaped piece s of wood with a screw devidce that slowly spreads them out and retracts. it’s worth owning, i think mine was 7-8 dollars. i use it often.
i often wear a hat because im scaredycat and i am concerned about skin cancer.