The reflex housing has a prism mounted above a condenser and ground glass screen. The prism can be rotated. There is normally a coupling between the shutter release on the camera and the reflex housing. This example has a Leica thread.

The bellows are a special unit for use with the reflex housing.

The Visoflex I was introduced in 1951 and replaced the Mirror Reflex Housing (PLOOT) it was discontinued in 1962. Available in both screw and bayonet fittings.

The Visoflex III was introduced in 1963 in a bayonet mount for the Leica M. It had the advantage, over the Visoflex II, of being fitted to the camera without having to remove the pentaprism; the lens mount on the Visoflex was pushed into the body of the Leica and a lever turned to lock it in place.

The mirror has three settings: slow rise of the mirror, the mirror is raised by finger pressure on the release lever; fast rise, the mirror trips and is raised by a spring; mirror lock up. When set to fast or slow the mirror returns to the down position once pressure on the release lever is removed. For very long or time exposures it was best to use a cable release, when one is fitted, the mirror operates at the slow setting.