You must be logged in and verified to contact the designer.
These are a variant of the standard slate wagon coupling, but are of longer, narrower, more rounded profile to reduce shock impacts between wagons. They can be found of some slab, bolster and slate wagons. Supplied as a pair, which will need separating. Attach the tail with a 16BA nut and bolt. (or even better, an M0.8 hex headed bolt from Prime Miniatures)