Personalized Smart Mechanical Engineer Youth 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. Let the good times roll in a durable T-Shirt that takes kids from school to play in an amazing array of colors. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar.