The Giro Atmos Road and Racing helmet provides legendary performance, style and comfort - and features the new Roc Loc 5 fit system. After more than ten years of refinement, this ground-breaking fit system provides an entirely unique use experience with an unmatched level of comfort, stability, adjustability and weight savings. With Roc Loc 5, you can easily dial-in both fit tension and adjust vertical position with a single hand. Just twist the dial for a tighter feel on tough terrain, then back it off a notch and relax across the flats or a warm climb. Even with these remarkable features, Roc Loc 5 is still 40-percent lighter than its popular predecessor, Roc Loc 4. Roc Loc 5 systems is: 1) Micro Dial. The heart of the Roc Loc 5 is this ratcheting, micro-adjusting dial. A simple, two-finger twist of the Micro Dial opens or closes the retention system and each click is audible. 2) Three-Position Vertical Fit - It's never been easier to change vertical positions and fine-tune fit. We incorporated a three-position bracket that features 15-millimeters of precise up/down movement. Like the Micro Dial, this system can be adjusted without removing the helmet. 3) Carefully crafted ergonomic arms are shaped to be as comfortable as possible, yet work flawlessly with Giro eyewear (what we call Super Fit engineering). 4) Dual Pods - These two panels are designed to firmly grasp the back of your head while comfortably cradling the occipital lobe. Strap management - with Roc Loc 5, your helmet straps are woven through the fit system, so they are always in the perfect position. Complex Internal Design - Dozens of small parts work together seamlessly to provide exceptionally user-friendly adjustment. Minimal and Light, yet Strong - Although this fit system is 40% lighter than its predecessor, it's much stronger. In testing, Roc Loc 5 performs flawlessly, even after 6,600 cycles (equivalent to 3 years of riding with 3 round trips per day).