These are 14mm Marker Piston Plates. I pulled them yesterday from a pair of older speed skis, which had proved to be dog slow, and have been sitting unused for 5-6 years. Will now become part of a bench.
These were just mounted on that one pair of skis, mounted once with bindings, and skied about three days. They are really like new. Perfect. Even the foam on the underside looks new.
PM me with any questions. I have a few more pics, if needed. Thanks!