Personalized Mechanical Gears T-Shirt. Mechanical Engineer in gray text and a row of gears below will put your favorite engineer in gear for the day. Unique gift design for your mechanical engineer at birthdays, holidays and graduations. 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.