Tour Tongue Dual Density LinerDesigned to have a high range of motion for backcountry touring and telemarking, these dual density, lightweight, soft flexing liners save energy on the way up and provide unparalleled responsiveness on the way down. Tech Specs Fully heat moldable Intuition Foam Low DD toe box 4mm HD non slip outsole 4mm HD foam shim insole 4mm MD internal J bars for ankle support and heel hold Rear flex zone Locking speed lace system Extra abrasion resistant fabric