Personalized 12th Anniversary Celebration Party Long Sleeve T-Shirt. 12th Anniversary Long Sleeve T-Shirt - White with words Celebrating Our 12th Anniversary for a 12th Anniversary Celebration. Pre-shrunk 100% cotton 6.1 ounce long sleeve t-shirt. Double-needle stitched neckline and sleeves. Quarter turned. Shoulder-to-shoulder taping. Adult: S, M, L, XL, 2XL, 3XL