After the Flexaret III Meopta changed back to a knob driven filmtransport, most likely not because of issues with it but rahter because of the price. The knob style was also easier to use and it gave Meopta the oppertunity to step away from the classic red window still used in the Flexaret III. Further changes were made in the form of the Lens, a new Tessar type lens called the Belar replaced the older Triple type lens Mirar. The Belar lens would serve on all later types of Flexarets. Other changes consisted out of:
- The system to hold the back latch changed
- The focussing lever was made more sturdy
- Shutter changed from Prontor-S to Prontor-SVS (and thus losing the T-function on the lens)
- The 2 knobs on the side dissapeared, the loading of the film was now done by swinging out a metal holder at one side and the take up spool was put in place by pulling the transport knob.
- The main shutter release was no longer on the shutter itself but on the front of the body, however there was still the oppertunity to release it on the shutter itself. Underneath the main shutter there was a treated hole to use a cable release.
- The viewing hood was also changed, this consited out of a 2 piece construction that slides open, the magnifying glass was moved to the back of the hood. To reach the ground glass one didn't have to screw the hood off anymore, it was now reachable with screwing off the name plate of the Flexaret.
All in all the Flexaret IV was a serious upgrade from the Flexaret III, not only because of the improved lens but also on the many other improvements that made the camera a lot more stronger. On the other hand, the new shutter linkage made the camera a little more complex to repair.
The Flexaret IV uses 30mm push on filters which are quite widespread.