Some gadgets of the past were feats of engineering that managed to squeeze countless moving parts into small packages. This diagram of the classic Nikon F3 shared by Bellamy Hunt of Japan Camera Hunter is a glorious sea of mechanics.
On his website, Hunt details how he came to be in possession of the poster, which looks to be a reference for repairing or servicing the camera, and how he fell head over heels for vintage film cameras in general. Looking at the spread truly makes you appreciate the intricacy of such complex devices.
The particular model in the posted is the Nikon F3-P, which came out in 1983 and was geared toward press photographers. I wouldn't hesitate to hang this poster on my wall. Check out the great site Japan Camera Hunter for more of Hunt's wheelings and dealings with all kinds of classic cameras.