Invention:

"Modern snap fasteners were patented by German inventor Heribert Bauer in 1885 as the "Federknopf-Verschluss", a novelty fastener for men's trousers".

And so, any Verlangerungsmesser sheath with the snap button strap is probably post (after) 1885.

Last edited by C. Wetzel-20609; 01/16/2023 09:01 PM. Reason: added another comment.