SixSixOne Sub Gear Short Sleeve Shirt (Black, X-Small) Mesh window in the upper back area for added breathability Sub Gear utilizes an anti-microbial 4-way compression fabric called Dri-Kool Wicks moisture off skin while keeping the rider cool, even on hot days Strategic amounts of Intella-Foam are light and absorb sudden hard impacts more than traditional EVA foam four times its thickness Flat-lock stitching eliminates irritating seams