The off-road world is a dirty, tough place. Chunks of rock and dirt mean business when launched by roosting tires, and even when it's muddy, hitting the ground is always hard. That's why Bell sweated the details on the MX-9, loading it with a tough polycarbonate shell, MIPS energy management system, an adjustable visor, Velocity Flow Ventilation, and a removable, washable, anti-microbial liner for when the time comes to hose down. The MX-9 MIPS packs all these features into one helmet, delivering exceptional value and pro caliber performance. -Lightweight polycarbonate / ABS shell construction. -MIPS energy management system. -Three shell and EPS sizes for a personalized fit. -Velocity Flow Ventilation system for maximum cooling. -Fully adjustable Flying Bridge Visor with air intake vents. -Removable / washable anti-bacterial interior. -Integrated roost guard. -Padded chin strap with D-ring closure. -Industry-leading five-year warranty. -Certification: DOT, ECE. MIPS: Time Is Everything - For the past 60 years and counting, Bell engineers have researched the forces involved in crashes across a wide range of scenarios. Recent findings have concluded that brain injury received during an angular impact is much more severe, due to higher strain on the brain's tissue. MIPS addresses this strain by allowing the head to slide independent of the helmet for a few milliseconds. This critical moment of time helps to reduce the violence of the brain inside the skull, and can significantly reduce the risk of traumatic brain injury. How It Works - MIPS uses a slip-plane system that moves inside the helmet, mimicking the brain's own protection system. This layer is designed to rotate inside the helmet with the intent to potentially slow or reduce the amount of energy transferred to or from the head. Science tells us that if Bell can reduce the strains associated with rotational acceleration, they might reduce the risk and severity of brain injury. Why It's Important - When a head rotates quickly and comes to a sudden stop, the rotational acceleration can cause the brain tissue to experience high levels of strain. The stretching of the tissue that can be caused by these motions can result in various types of brain injury. Bell believes that helmets equipped with MIPS technology can provide an additional measure of protection in certain impacts.