Personalized Cowboy 6th Birthday Women's V-Neck T-Shirt. Cowboy 6th Birthday Women's V-Neck T-Shirt - Aqua has number six wearing a cowboy hat with lasso and I'm 6 birthday quote. 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