Tiny Nikon cap--what is it?

[Patrologia]

Yesterday I bought a Nikon EM, and assorted equipment. Ok, really I bought a 24mm 2.8 Nikkor, and there was an EM attached to it. Anyway, among the assorted odds and ends in the box was a tiny cap, slightly larger diameter than a nickel. It says Nikon on it, and also says EE. Google hasn't helped, the EM manual didn't seem to mention it, and I can figure out what it covers. Anyone?

 

[macfred]

Those EE caps (27mm diameter) are from a Nikon binocular I guess.https://www.ebay.de/itm/Nikon-Ferng...362501658314?_trksid=p2385738.m4383.l4275.c10
https://www.ebay.de/itm/Nikon-Ferng...362501658314?_trksid=p2385738.m4383.l4275.c10

 

[Patrologia]

Wow, good find! I do wonder how that got in there. I may call the seller and ask if he has a pair of binoculars missing a cap.
Danke!

 

[macfred]

Bitteschön!