Personalized Monster Truck 3rd Birthday Long Sleeve T-Shirt. I'm Three! A red monster truck drives over the words. Great third birthday gift for your 3 year old who loves trucks. 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