Personalized Lucky Unicorn T-Shirt. Cute St. Patrick's Day T-Shirt - Pacific Blue with magical, green Irish unicorn and shamrocks says LUCKY. Luck O' The Irish unicorn lover novelty gift for parades and Irish St. Paddy's Day parties. 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.