Description The OneK helmets are available in 3 shell sizes. By using the OneK MIPS liner which is available from XXXS to XXL you can achieve the perfect fit. The OneK liner is made of a washable quick-dry fabric; it is moisture wicking and anti-microbial. Technical description: The One K ™ helmets are subject to three different tests. One K ™are proud to score above the required standards in all tests and thereby being approved by the CE norms VG01 and ASTM F1163-15. Product ID: 343306 Product reviews (0) OneK MIPS Oval Winter Helmet Liner