High-exertion workouts and high temps don't always play nice together, unless you're rocking a piece from the Echo Collection. Built with UPF sun protection, AirVent moisture management, ActiveFresh odor control technology, and topped off with an anti-chafing flat-seam design, the Echo Collection is the smarter way to tackle the heat. From sun-scorched desert climbs to sweltering ultra runs, the Echo is your perfect balance of tech-packed performance and ultralight protection. Airvent 100% Polyester. Center Back Length: 27 1/4a 69 cm. Weight: 3.2oz 91g Avg weight for size M. ActiveFresh active odor control. Wicking. UPF 15 Sun Protection. Flat-seam Construction. Raglan Sleeves. Reflective Logo. Machine wash. Imported.