Silver Hair Iron Core Funny Workout Gym T-Shirts for Men, Gym Shirts, Gym Gear, Gym Apparel, Gift for Weightlifters Gift for him Upgrade your workout with Silver Hair Iron Core Funny Workout Gym T-Shirts for Men. Made with 60% cotton and 40% poly, providing a comfortable and regular fit. Its manly fashion cut with side seams adds to its stylish look. This shirt makes a great gift for any man who loves working out.