Built with all-mountain exploration in mind, the Union uses in-mould construction to make it lightweight and a fully adjustable venting system to control the airflow for varying weather conditions. Giro’s category-leading In Form fit system allows for a more precise and comfortable fit and MIPS reduces the effects of rotational forces from an oblique blow.Size GuideSmallMediumLargeX-Large52-55.5cm55.5-59cm59-62.5cm62.5-65cmClick here for more information on our Size & Fit GuideVenting: ActiveSizing System: AdjustableWeight: 475gConstruction: In-MouldSafety standard: eN 1077 Class BAdditional SafetyMIPS can provide more protection in certain impacts. The main components of a MIPS equipped helmet are 1. The Interior Foam Liner, 2. the Low Friction Liner and 3. an elastomeric attachment system. In an angled impact, the elastomeric attachment system stretches to allow the foam liner to rotate independently around your head.VentingThermostat Control adjustable venting allows you to custom tune airflow instantly with a simple, low profile button on the outside of the helmet.Stack Venting was developed based on research showing the majority of the warm air that can cause fogging exhausts from the centre top vent of the goggle. Aligning the Stack Vent in the helmet with the vent of your goggles helps to keep them clear and fog-free.Sizing SystemThe In Form system makes it easy to dial in a custom fit in seconds, even with gloves on. An ergo-friendly dial at the base of the helmet provides up to 6cm of adjustment and enhanced stability. The Vertical Tuning feature accommodates different goggles and head shapes for a custom fit free of gaper gap.ConstructionIn-mould construction fuses a tough polycarbonate outer shell with the helmet\'s impact-absorbing foam liner. The fusion process allows for better ventilation systems, making in-mould helmets lighter and cooler than traditional helmets.