New with tags! Still in its original unopened plastic packaging. Size Medium JCrew Boatneck Muscle T-Shirt in Mariner Cotton fabric Color: Carter Stripe in Sands/Burgundy Elevate your tee collection. We took our customer-favorite mariner cotton (a lightweight-but-durable fabric that feels like your favorite rugby) and dressed it up with cap sleeves and a tapered waist. 100% cotton.