I bought this hat in small/medium size and find it a bit on the small size - it slips up slightly over my ears but does stay on my head to give me overall warmth. I think the medium/large would be too big though. Ideal fabric for me as wool is too itchy for me! I will go on wearing it as it was just what I wanted and it may stretch a bit after several wears! Bought it with an offer price which also helps!