There are two styles I have seen. one is a cheepo set of bent, chromed
steel that resemble an "8" when the two are put together.. the other, MUCH more elegante set has an upper piece machined (cast?) out of good alloy that polishes up nicely, with a lower matching piece that appeares to be the same lower as the other set uses.
Stock piece on 74 Eldos near as I can tell. Also a much earlier version used on V700s and some early Ambs, so there is actually 3 different types.