Personalized About The Shamrocks T-Shirt. St. Patrick's Day T-Shirt - White with shamrocks and confetti says IT'S ALL ABOUT THE SHAMROCKS. Perfect for St. Patrick's Day celebrations and parades or for anyone who loves shamrocks. Everyone loves our Custom T-Shirts! 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.