NBW Baselayer Short Sleeve Top Good for everything from light stretching to high-intensity workouts, the New Balance W Baselayer Short Sleeve Top is a staple in any athletic wardrobe. Made from lightweight polyknit materials with moisture-wicking NB DRY technology, it helps you stay cool and focused on your workout. This compression top has a fitted silhouette that is easy to layer and designed to let you move freely without getting caught up in extra fabric. 74% polyester, 26% spandex.