CONSTRUCTION - Hard Shell construction produces great helmets at great value. A rugged outer shell is formed and then attached to the EPS foam liner. FIT SYSTEM - Auto Loc 2 Fit System (removable) is a durable self-adjusting fit system designed to take the hassle out of fitting a helmet. A supple elastic fit band at the back of the helmet merges with fixed-position straps, which adjust to cradle your head when you set the system to one of the 3 different circumference settings. The new On-the-fly Vertical Tuning feature helps to dial in your fit and goggle set up without removing your helmet. VENTILATION - Stack Vent in the front of the helmet which aligns with your goggles and helps to keep them clear and fog free. The Super Cool Vents on the top of the helmet allows the hot air to escape. SEAMLESS COMPATIBILITY WITH ALL GIRO EXV GOGGLES - Giro products have been meticulously designed and tested to work together. We've fine-tuned the pairings of our helmets and goggles using exhaustive testing in our Dome R&D center and translating those findings into the perfect Seamless Compatibility fit. We recommend Giro Axis, Ella, and Blok Goggles. FEATURES - Compatible with aftermarket audio systems. Removable ear pads. Removable goggle retainer. Vertical Tuning.