Lightweight Gravity+ outsole delivers awesome cushioning and traction, with a rubber toe-tip to boost grip when hiking over ice and rock; Transition Zone tech seamlessly connects the Altai's sole to the Exo Spine, accelerating response and preventing damage to the back of the boot when entering or exiting the binding; Heat-moldable Silver Liner allows you to customize the fit if you need to but is comfortable straight out the box; Dual BOA technology provides quick, precise lace adjustments via two independent dials. Each controls a distinct boot zone, delivering a custom fit in seconds; Bombproof BOA H4 Coiler increases the speed of entry and quickly takes up lace slack; Awesome foot hold that starts right inside the liner, with 3D molded material and J-bars around the ankle; Pull the inner laces to tighten a shell-mounted harness. Velcro secures the tongue; 3D Dual Density Insole is constructed from two densities of EVA, with firmer material supporting the heel cup and arch; 3D Toebox eliminates extra layers and seams around the forefoot, improving water resistance and durablility; Asymmetric 3D Molded Tongue features a sharper curve on the medial side to match your natural forefoot shape