Personalized Boss (Worlds Best) T-Shirt. Worlds Best Boss T-Shirt - Vintage Royal Blue has cool sports style logo, a great gift for your boss at holiday time or to say thank you for making your office a better place to work. 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.