A very rare camera because only a very small number has the black top while most were chromed. To some people it is the best and most innovative rangefinder ever produced by Olympus or any other maker. When it came out in 1969, it was the only rangefinder that had both center weighted and spot metering features and thereafter no one except Leica followed suit with one. The "F" ring and the shutter speed ring work in tandem and so you can select your DOF and the corresponding shutter speed with a single twist. (5 years and 1969 days ago)