Personalized Country Code Mexico Long Sleeve T-Shirt. Mexican pride Long Sleeve T-Shirt - Charcoal with the three letter country code for Mexico, MEX, and the flag of Mexico. Perfect for Cinco De Mayo. Pre-shrunk 100% cotton 6.1 ounce long sleeve t-shirt. Double-needle stitched neckline and sleeves. Quarter turned. Shoulder-to-shoulder taping. Adult: S, M, L, XL, 2XL, 3XL