Personalized Future Firefighter Like My Uncle T-Shirt. When I grow up I'm gonna be a firefighter like my Uncle T-Shirt - Navy Blue for nephew or niece Wardrobe essential for looking good, 24/7. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar. Shoulder-to-shoulder taping. Double-needle stitched sleeves, bottom hem and front neck. Note: greys are a cotton/polyester blend.