The Pace Air Tank is built for high-output activities like running, fast-paced hiking, and mountain biking in warm or humid weather. Constructed from Rerun Jersey — an ultralight, stretchy fabric woven from 100% recycled polyester — the tank features a superfine knit that resists snagging and wicks moisture quickly to keep you comfortable over extended efforts. A slim athletic fit and flat, strategically placed seams ensure freedom of movement with minimal chafing throughout.