Salomon Nordic System boots come in two different options: Profil and Pilot (the backcountry variant of SNS, X-ADV, was retired in 2015). All SNS boots have a bar at the toe and a single channel along the sole of the boot. SNS Profil boots have one bar, while SNS Pilot boots have two-one at the toe and one at the ball of the foot. SNS Profil and SNS Pilot boots are not compatible with the same bindings