Personalized Smart Mechanical Engineer Long Sleeve T-Shirt. Mechanical engineering, the profession for intelligent people text with the E in engineering wearing a hard hat, is a humorous design with attitude for college students and engineers at back to school, birthdays, holidays 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