A classic 50mm finder for Leica. Product code is SBOOI, later changed to 12015.
A masterpiece by Leitz, known for its simple functional beauty and outstanding clarity.
This example features the 5cm marking and is an early version with lowercase engraving.
There are nearly eight known variations of the SBOOI, and this one has a black-painted eyepiece, a single grub screw on the shoe, and knurled grips on both sides of the finder body.
The black paint on the edge of the eyepiece side has worn thin, revealing the underlying brass. There are also two tiny marks on the chrome surface and a few very faint scuffs, but overall, it still retains a clean and attractive appearance.
The glass is clear and bright, offering the superb view typical of the SBOOI.