The Pearl Izumi Men's Barrier Skull Cap is a snug and streamlined full head cover with a wind resistant front panel to keep you cozy in the thick of winter. This head cover is precisely tailored to fit under a helmet as its mildly scalloped back prevents fabric bunching while in the cycling position. It is made with P.R.O. Thermal Dry fabric that provides quick-drying warmth, reflective elements enhance safety, and an otherwise hidden rear port opens as needed to accommodate a ponytail. When the cold weather hits, the Pearl Izumi Men's Barrier Skull Cap is there for you!