Personalized 21st Birthday Gift Women's V-Neck T-Shirt. 21st Birthday Women's V-Neck T-Shirt - White has colorful bday balloons and slogan that says Party - 21 Rocks. 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