The Madison Isoler Mesh Sleeveless Base Layer. Fast wicking technical summer weight base layer for warm weather riding. Open mesh fabric aids air flow to prevent over heating.  Madison Isoler Mesh Sleeveless Base Layer Features The 3D back to the fabric reduces contact with the skin to aid airflow, and in turn keeps you drier For ultimate comfort, circular knit construction means you don't have any seams running the length of your body Soft binding on neck and arm opening Race fit, designed to hug the body