A ski equipped with an interface device having a plate that is kept raised above the upper surface of the ski with a front portion, a rear portion, and a non-extensible linkage. The ski has in its middle sliding skid zone a zone where its two lateral side edges are substantially parallel, each of the portions of the plate being connected to the ski via two lower wings that extend beneath the plate, both wings being pressed against the lateral side edges of the ski, and each wing being fixed to the ski via a single binding journal element. The invention also is directed to an interface device and a ski considered separately.