Simplicity has always been Mountain Hardwear's guide to the mountains?and their focus for designing headwear for high-alpine environments was no different. The Dome Perginon™ Pro is engineered to work with your helmet, so it fills a gap in your kit without complicating the rest of the system. It's sleek yet notable. It's effective yet humble. It's why their dome hats have been favored by alpinists and big-wall climbers for a quarter of century and counting.