Vast. Aqua Terra Vast Tech Tank Our Tech Tank ranks as one of our best sellers and delivers unmatched comfort for any occasion. The patented Aqua Terra fabric features a blend of 96% recycled polyester and 4% elastane. Beyond what you see, the "stretchy" Aquaterra fabric adapts to your body, provides 50+SPF sun protection, wicks away moisture, resists microbes, and dries quickly. Style meets comfort and sustainability all in one shirt.