I knit this ribbed hat using a wool yarn. It is a suitable style for both men and women. It fits beautifully because of all the ribbing knitted into it.
The chartreuse stripe is a bit of alpaca yarn that I dyed myself.
Without stretching, it's 13 inches/ 33 cm around the bottom and 8 inches/ 20 cm.tall. I have an average 22 inch head and it fits very comfortably, coming down and completely covering my ears.
To wash, soak for about half an hour in hot water with a dash of soap (Dawn works fine). Squeeze water out gently and soak in warm water to rinse. Lay flat to dry. To prevent shrinkage avoid agitation and extreme water temperature changes.