Shift Cycle Wear National Park Foundation Official Tech Tee 10% of sales proceeds donated to The National Park Foundation Micro-poly blend is breathable, and efficiently wicks sweat from your skin and hastens its evaporation Dries quickly so you won't feel chilled by a strong sudden breeze or feel clammy on hot or humid days Comfortable design and fabric allows for fluid, unrestricted movement Relaxed-fit shirt works tirelessly to optimize your comfort during high-energy activity