Personalized Farty Forty T-Shirt. You're farty! I mean forty. Happy birthday, you old fart. Funny gift for your favorite 40 year old's flatulent 40th bday. Everyone loves our Custom T-Shirts! 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.