Ski base and running surface

An elongate body for a ski which defines a longitudinal axis and a transverse direction generally perpendicular to the longitudinal axis, the body for the ski comprising:

• generally opposite top and attachment surfaces,
• said body attachment surface comprising a structured surface extending transversely across at least portions of the ski body for releasably and repeatably attaching the ski body to a reusable ski base sheet having generally opposite running and attachment surfaces,
• the structured surface comprising a common plane or surface, and a plurality of tapered elements, each element having at least one side inclined relative to the common plane at an angle sufficient to form a taper,
• wherein the structured surface of the ski body is adapted to frictionally adhere to a structured surface of the attachment surface of the reusable ski base sheet,
• wherein the tapered elements have a geometry including a height and cross-sectional shape,
• the ski body has a length along the longitudinal axis, and
• the geometry of the tapered elements along the length of the ski body is not uniform to alter the flexure characteristics of the ski body along its length when the ski base sheet is attached to the ski body.