Personalized Twice As Lucky T-Shirt. Irish Engineer, twice as lucky. Anyone can find a four leaf clover but you'll need an engineer to come up with a better, luckier, eight leaf specimen. Fun gift for birthdays, holidays and graduation. 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.