Nikon EM with its Series E 50mm F1.8, all 1st version.
It is my 7th EM.
Arrived pretty much in need of a cleaning and some exercise. It was covered in scars of many battles and dust was visible on the outside. It hadn't been worked for some years now. Had no batteries in it and I put new ones. No power was coming through. Took the batteries out and inspected the battery compartment. The cover had some green vestiges of previous batteries. So, it went to a bath of vinegar diluted in water. An hour later it was shiny clean. The same batteries went in and power was available.
The AI tab on the mount was lazy to return to its original position and it looked like it would need a new spring. But, a blast of air around the mount to clean it from dirt and some exercise on the AI tab side to side and it was working well again.
Everything else is working as it should. What fantastic little cameras they are!
* "So much time and so little to do. Wait a minute. Strike that. Reverse it. Thank you." (the original Willy Wonka: Gene Wilder, 1971)
* My favorite cameras: Leica SL, Leica M7, Russian FKD 18x24, Bronica SQ-B and RF645, Rolleiflex T2, Nikon F4s, Agfa Clack and my pinhole cameras