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Type 91 Naval Anti-Aircraft Mechanical Time Fuze
 

This is the Type 91 Mechanical Time Fuze, modified with a gear ring for automatic time settings. 
The body is made of nickle (?) plated brass and aluminum, with an  aluminum nose cap.
The fuze was used with ammunition for the 12,7cm AA-gun with an automatic time setting device.

There would be a data label on the lid. Saw a complete one at a gun show a while ago. While tempted to buy that one just for that I passed. Bothers me ever since ;o)
(Anyone have a scan of the label the goes on the lid ?)
While Army fuzes seem to have all kinds of useful data stamped on them, Naval fuzes seem to have very little. Here we can see "1-" followed by the serial number (also stamped on the gear) and what I assume to be the date "Showa 16-9" Sept 1941. 
Any idea what that character is following the 8 ? I cant find that one anywhere.

To the right is the Kana Character "To" followed by an anchor. I would think this is the mark for the Naval Arsenal that made the fuze, possibly the Toyokawa Navy Yard? Just a guess here. 
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