That is the most complicated 'simple' Krag sight, that I have ever seen.

I have never seen this item before. Nor do I recognize any origin or parts from another sight 'family'.

The 'Safety-Lever' is not a standard Springfield Armory 'Safety'. Part of this sight's retention may be a screw, that goes through the early 'grooved' Bolt-Collar and also retains the shaft of the Safety.

The double-screw "L"-shaped side-plates, appear to clamp the extractor, as a forward anchor point.

A mighty curious sight that was skillfully made!

The main body looks like it could have been machined from a Luger frame.

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