You'll be buzzing in the Under Armour Lacrosse Vibration T-Shirt.. It's Moisture Transport System will keep you dry in the heat of the game. But what good is this if it isn't comfortable, right? For that reason, the folks at Under Armour made this out of 100% Polyester material so that you'll never find a reason to take it off. Except if you want to wash it, of course.