The K2 Boundary snowboard boot features a dual-zone closure with BOA® Fit System to micro-tune your fit. A dedicated BOA® dial for the upper shell and a second dial dedicated to closing the lower part of the shell. The upper cuff of the boot is constructed with our HDR Premium Synthetics. It features a fully articulating design, upping the durability factor while reducing the distortion of the shell as it flexes forward.