Personalized Coolest Mechanical Engineer T-Shirt. The world's coolest mechanical engineer text with a snowman holding a gear and sporting a hat and scarf with gears is a humorous engineering gift design for birthdays and holidays. 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.