A small advice to avoid aftermarket parts

from time to time pop out Marsha bands on the Bay. These are real
1950 riveted bands of perfect quality because made by.... Gay frère like
the Rolex ones.
They come in 17/18/19mm and in expandable version only (at least from what I bought thru the years I only saw expandable ones).
The plate you see I bought complete for 60 usd on the bay, an ideal genuine vintage band to wait for the perfect Rolex one.

I personally use them as part source, I retrieve the "Z" springs impossible to find and my watchmaker refurbish my Rolex
riveted bands with it to get them perfectly tight.