PYNCap - Distance Nirvana protect your neck. leaning heavily on our industry standard GOCap, the PYNCap brings you extra protection for hot summer long runs where shade is hard to find and the sun is at its peak. the removable neck protection is made of COOLmatic|PLUS fabric for lightweight cooling, and its snap in snap out convenience makes the PYN the most versatile of caps for summers intense conditions. size: S/M 54-57 cm