Lachenal Anglo metal ends fretwork - is it unique for each concertina?

[Orm]

Forgive me if this was discussed before, but I couldn't find a thread about it.

Looking at different concertinas online I can't stop but wonder - how unique are concertina ends? In particular, I look at higher end Lachenal anglos with certain features - ebonized ends, inset metal ends. As far as I know, the dimensions of such concertinas are (mostly?) standard - 6 1/4 across flats. Still, I see quite a difference in the fretwork. 

It could be, of course, explained by production date difference - maybe they were making different ends during different years? But I just thought I'd ask - I'm quite sure there is a knowledgeable person here who knows everything about it.

For the reference I can add pictures of my 32-buttons Lachenal anglo:
 

Edited October 11, 2021 by Orm

[Stephen Chambers]

In one sense yes, because delicate fretwork like that has to be cut by hand - so each one is likely to be slightly different, but not significantly so.

 

Though they do seem to have made significant changes, periodically.

 

With the letters SA fret-cut in the cartouche, this one must have been made for the Salvation Army.