The Gewirette was a small viewfinder-type camera made by Wirgin in Wiesbaden, Germany. This collapsible camera (the lens collapses into the body to make it more compact) takes 127 film using a 5 cm lens. The specimen I have has a Gewironar f/4.5 lens, marked "Wirgin Wiesbaden". It has a 3-speed Vario shutter (1/25, 1/50, 1/100 plus T & B). The camera is interesting in that the entire top of the camera comes off to load and unload film; there's a winding knob (marked "F") on the left, and a latch knob on the right, marked "Z" (for "zu", closed) which you turn to unlatch the top and allow it to be lifed off the body.
The back has two red windows, covered by little spring-loaded hinged metal covers. The two windows are used together to locate the next frame to expose, by first lining up the exposure number in the righthand window, then by lining the same exposure number up in the lefthand window (the film winds from right to left). This gives 16 exposures on a roll of film.
The lens is a triplet, with the front element on a helical to focus (down to 3 feet).
The camera has "GERMANY" stamped in the vulcanite on the back, and the focus scale is marked in feet, so I assume it was made for export. (I obtained the camera recently in the United States.) It also has the standard American thread for the tripod mount (1/4") as opposed to the European standard 3/8".