Giro Shiv Snow Helmet Snow helmet designed in conjunction with several elite snow riders In-mold construction fuses tough polycarbonate outer shell with impact-absorbing liner EPS liner absorbs more impact energy gram for gram than other liner materials Super-cool vents pull cool, fresh air in and push heat and stale air out Comes in small (52 to 55.5 cm), medium (55.5 to 59 cm), and large (59 to 62.5 cm) fits