Personalized Santa Hat Brain Women's V-Neck T-Shirt. A happy brain wearing a Santa hat is a humorous winter holiday gift design for psychologists, neuroscientist, neurologists, neurosurgeons and medical students. 5.0 oz., 100% pre-shrunk cotton Athletic Heather is 90/10 cotton/polyester 1x1 rib collar with mitered v-neck Shoulder-to-shoulder taping Ladies' fit