Abstract: An attachment for skis, for preventing crossing of skis, includes a base plate for mounting on a ski, and a deflector which is releasably mounted on the base plate and which is pivotable thereon, under resilient biasing, from a lowered position substantially flat with respect to the base plate to a raised position upstanding on the base plate. The deflector is engaged releasably with the base plate by an axle passed transversely through the deflector and projecting therefrom at each end. The projecting ends of the axle each having a parallel sided portion of reduced width which, with the deflector lowered, can be passed into a keyhole aperture in a side wall of the base plate, whereas when the deflector is raised, the axle is retained in the aperture of the side wall. Releasable spring loading acts between the base plate and the deflector.