Personalized 1st Birthday Monkey T-Shirt. Go on a safari or zoo trip with this adorable number one 1st Birthday Monkey T-Shirt - Black. 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.