The spindle of the take-up spool of the bulk-film back attaches to the camera's film advance spindle using a coiled spring. This stretches between the underside of the bulk-film back and a short extension piece fitted to the bottom of the camera. A metal plate then attaches to the film back to cover the spring. With a motor drive in place the coiled spring fits into a slot in the motor drive.

The Praktina was the first 'system SLR' offering features such as motor drive and bulk film backs not found on the Exakta, and preceding the Nikon F by several years.

The first model (FX) was brought out in 1952 or 53, it had a semi-automatic lens diaphragm that had to be manually opened and tensioned after exposure by a lever on the underside of the lens. The diaphragm was kept open by a spring latched in the tensioned positioned, when the diaphragm pin was depressed the latch was released, the spring contracted and closed the diaphragm to its pre-set position. On the model IIA (1958) the diaphragm was automatic, it opened when the shutter was tensioned; a spring in the lens tended to close the diaphragm, it was held in the open state by a plunger in the camera body acting on the lens, during exposure the plunger was withdrawn (which allowed the diaphragm to close) and returned after exposure when the shutter was tensioned.

The lens mount is a breech lock type with the moving ring attached to the camera body, as on the later Praktiflex. There are variations and developments in the camera models.

In the early 1960s production was ended allowing KW to concentrate on the amateur end of the market with its Praktica range.

A large number of lenses was available, other accessories included:

• Bellows.
• Extension tubes, pre-set or automatic.
• Lens reversing ring.
• Rigid magnifying hood.
• Waist-level finder.
• Roof Pentaprism with selenium meter.
• Accessories to fit pentaprism: eye-cup, right-angle finder, magnifier.
• Lever-wind attachment.
• Motor drive, two versions - clock-work or electric.
• Bulk film back for 50' of film.
• Stereo prism and viewing eye-piece.