The Kiev 6C ( or later version Kiev 60) by the wide-spread opinion was derived from the Pentacon Six, a fairly successful East German medium format SLR, but, in fact, is not the same. It has a different mechanics and it is bigger. The only thing those cameras have in common is the P6 (Pentacon Six) breach bayonet mount.
Camera was produced by the "Arsenal" factory in Kiev, Ukraine. Most lenses designed for the Pentacon 6 will also mount on the Kiev 6C. This means that Kiev 6C users have access to not only Ukrainian glass, but also Carl Zeiss Jena and other lenses produced for the Pentacon 6 and even the Exakta 66 cameras (which were also derived from the Pentacon 6).
Here is a list of the lenses with P6 bayonet mount:
Some people prefer the 6C to the 60, claiming that it was a better made camera and also has the ability to accept 220 while the Kiev 60 only takes 120 film. The camera had its shutter button on the left side of the camera.