The original of Zenza Bronica was introduced in 1959, as a high end 6x6 SLR with built in quick return mirror. Model S, D, C, C2 were introduced soon after.
The Bronica S2 was introduced in 1965 as the final model of manual SLR with high many features. It has a double bayonet unit for the various interchangeable lenses.
The lenses 40 - 200mm which are normal lenses are attached to the helicoid of the focusing unit. It is possible to attach any lenses by using screw mount which is inside the bayonet. As the mirror has a special movement which divides it into two parts as it rises and returns up and down, it is possible to use short focus lenses.
The lenses of 300mm or longer focus have their own helicoid included and attach to the body direct instead of removing the focusing unit. For the S2, the standard lens is Nikkor P75mmF2.8, the photo that you can see here is with the Zenzanon 100mmF2.8 lens. There are several interchangeable lenses 40, 50, 80, 100, 135, 150, 200, 350, 500 and 1000mm. The shutter is focal plane, B, 1 - 1/1000sec. with X, FP automatic terminal. Film magazine is able to use 120 and 220 film. 100x100x140mm, Weight is 1780g