Arctic Cool Men's Vortex Vent™ Cooling Crew Neck T-Shirt. Size Medium. VORTEX VENT DELIVERS MORE AIR MOVEMENT AND MORE COOLING HYDROFREEZE X PROVIDES INSTANT COOLING BREATHABLE, COMFORTABLE FABRIC ENGINEERED TO RELEASE THE HEAT MADE TO KEEP ODORS AT BAY WICKS AND DISPERSES FOR RAPID EVAPORATION SUN PROTECTION IS STANDARD 94% Polyester 6% Spandex Mesh: 88% Polyester 12% Spandex