More aerodynamic than the Aro 3, this helmet also features large airflow zones. The helmet's very compact design is ideal for wheel-skiing, with a very flat rear zone, and also makes it easier to carry a rifle for biathlons. The ventilation zones are designed to allow air to pass through the helmet for optimum ventilation during effort. While it's a little less airy than the Aro 3 version, it's nonetheless a little more versatile for mid-season when temperatures drop. . The aérations above the temples are made to effectively block the temples of the glasses if they need to be removed. Adjustment is made very easy with the BOA® adjustment system, this knob on the back of the helmet provides even tightening around the entire circumference of the helmet. For protection, the inner part is made of lightweight EPS foam lined with a MIPS system. This concept is highly effective in preventing accidental damage in the event of a fall. It's a simple principle: a thin layer of plastic between the foams allows the helmet to slide a few millimeters in the event of a fall, effectively reducing the impact and loading the target area, thus minimizing the impact. The MIPS system has been proven in the field for several years now, and is now widely used on many helmets. The MIPS system has been proven in the field for several years now, and is now widely used on many helmets. < p>The MIPS system has been proven in the field for several years now, and is now widely used on many helmets. We chose this helmet for its versatility and very comfortable design for rollerskiing, and after testing it on a number of skis, we're very happy with it, whether on a ski wheel or on a bike: it's impressively comfortable to wear. To say the least, Oakley's design is magnificent, and the helmet's compactness has a lot to do with it. We opted for two colors: - Blackout, discreet styling and perfect for use on a ski wheel or bike path. - Retina Burn, which offers greater visibility when used on the road. Technical features: - Polycarbonate léger shell. - Arched support structure. - 360-degree headband wrap. - X-Static® forehead cushion. - MIPS protection system for protection against accidental damage. - BOA® FS1-1 system. Roller ski helmet Oakley ---Aro 5 Blackout