Built with MIPS Technology, the Ledge is built to last through jibbing, park-riding, and all mountain skiing without sacrificing optimal air flow. Auto Loc 2 Fit System A simple and durable self-adjusting fit system using an elastic back band and fixed position straps automatically cradles your head once you select one of three different circumference settings. Seamless Compatibility with All Giro Goggles For optimal performance of both helmets and goggles, Giro products are designed to work together. Ensuring a seamless interface between helmet and goggles offers exceptional fit and dependable, worry-free function. CE EN1077B Hard Shell Construction Hard Shell Construction produces great helmets at a great price. A rugged outer shell is molded and then attached to the EPS foam liner. Stack Ventilation Stack Ventilation was developed based on research showing the majority of the warm air that can cause fogging exhausts from the center top vent of the goggle. Aligning the Stack Vent in the helmet with the center vent of your goggles helps to keep them clear and fog free while maintaining total helmet and goggle integration.