Personalized Mechanical Engineering Genius Long Sleeve T-Shirt. Mechanical engineering genius text with a line of gears is a unique gift design with attitude for engineers and students at back to school, birthdays, holiday and graduation. Pre-shrunk 100% cotton 6.1 ounce long sleeve t-shirt. Double-needle stitched neckline and sleeves. Quarter turned. Shoulder-to-shoulder taping. Adult: S, M, L, XL, 2XL, 3XL