Designed specifically for: KETILL The KETILL 4-Season Helmet: Your Ultimate Companion for Fatbiking and Summer Cycling Adventures. The KETILL helmet goes beyond being just a cycling helmet. It's meticulously designed for fatbike enthusiasts, winter cyclists but also summer riders, offering a perfect blend of top-notch quality, lightweight construction, and cutting-edge technologies. With its two-piece structure and integrated ERT™ system, the KETILL effectively reduces both rotational forces and linear impacts at high speeds. It's lightweight yet incredibly durable, making it the ideal choice for avid riders. The helmet features 14 large vents, ensuring optimal comfort by regulating temperature. Protect your head from both linear and rotational forces during your winter and summer adventures with the KETILL helmet. The KETILL also boasts a multi-position visor, seamlessly compatible with ski goggles, delivering exceptional versatility for winter fatbiking enthusiasts. Ride all year round confidently, knowing that your safety is our top priority. Choose the KETILL and explore the trails with peace in mind, whether you're on a fatbike ride or a summer cycling adventure. ERT ™ is a patented technology. SPECIFICATIONS Equipped with ERT ™ system 14 large ventilation zones Integral molded construction 2-piece polycarbonate shell and EPS structure Sealed, flexible pads Easy-to-adjust, comfortable, flexible straps with adjustable camlock Three-position visor ski goggles friendly Size S/M (54-59cm) Weight: 350g Size L/XL (58-62cm) Weight: 360g You wonder where the word ''BLIVET'' comes from and what ''KETILL'' means? Click on this link to find out.