evo.com | Nitro Snowboard Boots > The Nitro Sentinel Boa Step On Snowboard Boots are dialed and ready to go. Equipped with Step On technology and an easy to adjust BOA fit system, the Sentinel features a medium flex for control and comfort on your next cruise sesh. Flex Rating 5 (1 Soft - 10 Stiff) Nitro Step On(R) Outsole Step On(R) compatibility with up to 30% recycled rubber Single BOA Fit System Top to bottom even fit. Armored Spine Long-lasting heel fit Cloud 3 LIner Classic fit and comfort with Nitro's signature materials & design concepts in a lightweight, affordable package. No compromises on fit! | Nitro Sentinel Boa Step On Snowboard Boots 2027 - 10.5 in Brown | Rubber