This camera is
equipped with the security system which locks the shutter
release as long as the lens is not in position (see the picture aside).
This special system is present only onto the last versions of the
Ultra-FEX.
Because of its Bi-Format capability, two flaps are present on both sides
of the lens. They had to be positioned when using a 6 x 6 format film.
Circa 1960, this camera receives some slight modifications :
disappearance of the holes for loop, larger viewfinder, new range of
shutter speeds : 1/25 sec, 1/50 sec et 1/100 sec.