Periscope Lens ?

[Jesse Rocco]

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I'm trying to identify this lens. The glass itself magnifies and is 30mm thick. The entire diameter across is about 120mm. My wishful thinking is that it might be the head lens to the "sky" or "navigation" periscope possibly.

Any feedback or pictures would help. Thanks Much as always Gents - Jesse

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[Jesse Rocco]

2 more pics

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[Jesse Rocco]

Photos ?

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Searching for any photos that show the top lens of the "sky" or "navigation" periscope. The one pictured above is all I can find and its not the best.

Any help would really be appreciated, this is a tough part to research. Thanks Gents !

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