Liner The removable inner boot, usually made of foams, leather, plastics and textiles; provides padding for the foot to protect it from the rigid shell
Shell The plastic exterior of the boot, usually comprising two components: the cuff and the lower shell
Footbed The removable platform—located inside the liner—on which the foot rests
Bootboard The platform inside the shell on which the liner rests, usually removable; also referred to by its Italian name, zeppa
Lugs (toe and heel) The portions of the shell’s sole that interface with a ski binding. Must meet industry standards for size and shape (DIN compatibility). Sometimes replaceable in the event of excessive wear.
Cant The lateral (side-to-side) angle of the boot in relation to the ski. Boots can be canted to lean inward or outward, usually by grinding the sole at an angle, to give the skier better access to all four ski edges.
Last The shape of the interior cavity of a boot. “Last” is an old cobbler’s term for the footlike form around which shoes were once crafted.
Shaft alignment The lateral orientation of the cuff in relation to the lower shell; usually adjustable on at least one side of the cuff, so that the cuff can be angled to match the angle of the skier’s lower leg