84 mm rollers are probably the most versatile outdoor fitness equipment available on the market. But we'll let you decide. In 2022, the K2 84 mm fitness series features an entirely new upper material that fits comfortably on the foot while being breathable and performance-oriented. The aluminum frame ensures stable and agile riding with its more direct power transfer. The F.I.T. 84 BOA stands out from the competition with its award-winning Boa closure system, which quickly and easily wraps around the entire foot. Thanks to a multitude of clever details, the K2 F.I.T. 84 BOA will help you achieve your fitness goals.