The first Giro Nine helmet was introduced in 2001, and has remained a staple of Giro's wintersports line-up ever since, and for 2018, the anti is upped yet again. As was the original, the new Nine's in-mold polycarbonate shell construction keeps weight down and strength up. That shell's design has been re-shaped into a sleeker, lower-profile design, too, and integrated into it are both Super Cool vents with Thermostat Control adjustability and Giro's Stack Vent up front to keep goggles from fogging. The Nine also utilizes Giro's In Form Fit System makes it easy to dial in the perfect fit, even with gloves, while the Vertical Tuning feature can accommodate a wide variety of both head and goggle shapes. Rounding everything out is the helmet's compatibility with all aftermarket Giro audio systems so you can keep the jams pumping. The Giro Nine helmet comes in Matte Dark Shadow, Matte Black, Matte Blue, Matte White, and Red. The available sizes and their dimensions are below.