The EST Microlite Quarter Zip Pullover is designed to optimize performance. Crafted with 92% Polyester/8% Spandex, it offers superior 4-way stretch, enhanced range-of-motion, and integrated thumb loops. Additionally, its Shield 4 Sun™ UPF 50+ Treatment, Shield 4 Coolant™ Treatment, Shield 4 Odor™ Treatment, and Shield 4 Stains™ Treatment give superior protection from the elements.