NavList:

Hi, I recently purchased a second-hand Astra IIIb, and in addition to a normal scope it came with the item shown in the attached picture, which is clearly meant to be attached as a scope.  Anyone know what it is - purpose, use, brand/manufacturer?

My first thought was that it was a night-scope, maybe to see the horizon after sunset, but it doesn't appear to make the night any brighter and using it for stars or the moon doesn't seem to offer any benefits to just using the normal sextant.  

There is a normal eyepiece that you look through (the medium one) and a large cylinder with a tiny peep-hole.  The eyepiece can be turned for focus, and the larger cyclinder can be turned a few times in either direction, moving in and out, but not adjusting the size of the tiny hole at its center.  When you look through the eyepiece when turned on, everything is shown green. The much smaller forward-facing item on top emits a red beam that can be "focused."  Maybe this is meant to reflect off some distant, reflective bouy or mark or ship?

It takes a standard 9v battery. There are no markings or indications of the manufacturer.

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