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 a completely new upper material that fits comfortably on the foot while being breathable and performance-oriented. The aluminum frame provides 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 variety of clever details, the K2 F.I.T. 84 BOA will help you achieve your fitness goals.