Stiff enough for serious freeride enthusiasts, the K2 Thraxis Boa Snowboard Boot serves up high levels of energy transfer desired by hard-charging riders. It's also more adjustable than virtually any boot on the market thanks to the three separate Boa dials that give you complete control over the shell's upper and lower zones, as well as the boot's internal lacing. The H3 Boa Focus system delivers dual-zone tightening for dialing in your ideal fit. Controlling internal lacing, K2's patented Boa Conda offers on-the-fly liner adjustments to comfortably lock down your ankle and heel from lifting. The boot's Intuition Comfort Foam 3D liner is fully heat moldable for a truly custom fit without pressure points, while moldable internal J-bars lock-down your heel to prevent unwanted lift or excess movement within the boot. Plus, SpaceHeater technology in the liner also traps precious body heat to combat frozen toes. The dual-density EVA footbed cushions the blow of heavy landings with its supportive, dampening powers. And because the Thraxis is meant for hardcore use and abuse, K2 engineered it with an Endo urethane exoskeleton that resists breakdown and retains flex better than traditional stitch-and-glue construction. Rounding it out, an insanely grippy, lightweight Vibram V4 outsole maintains sure-footed hiking on some of the most treacherous types of snow.