These are all numbered and the brass part is 10 mm, the steel part is 12 mm. Made by the German company of Flume. Any ideas please? Thanks.
Probably pin gauges. measure the thin wire piece and see if it agrees with the number stamped on the brass part.
Many thanks for all your help, as an Englishman I award you the Sherlock Holmes prize for solving the mystery! I still have a bunch of Lorch, CWZ and J Thomas fine tools to correctly identify but I think I've pretty well figured those out.