THREE brand new unused original WRENN 'shoulder' screws designed to screw 'home' but not to nip tight on the moving part being held in place, such as a pony or bogie wheel chassis or the trailing bogie and coupling bar.
There is ONE 'large' shoulder screw which was used on the rear of the Stanier Duchess and Gresley A4 locos with a deep shoulder to carry the movement of the rear trailing bogie and the coupling bar for the tender. The TWO smaller screws were used for almost all of the other 'retaining' jobs such as the permanently connected loco and tender bars on the Royal Scots, the 8Fs etc. as well as the front bogies on the A4s, the Duchesses, the 2-6-4 Tanks etc.
Very useful to have in reserve or perhaps these are the screws you have already been looking for to replace the ones that are missing? Also suitable for Hornby Dublo locos.