The Rollei XF35 is a small 35mm full frame Rangefinder camera released by Rollei in 1974. The same camera can be rarely found under the brand Voigtlander: in this case it's called VF135.
This camera provides only a programmed exposition, with a CDS cell powered by a small 1,35v PX 625 mercury battery. A ring around the lens must be setted to a right ASA/DIN value.
The shutter is a small Copal central type one, that also works on relative aperture.
The lens is a Carl Zeiss Sonnar-derivation, built under license by Rollei. It's a 40mm f2.3, with focus from 1 meter of distance. The viewfinder has a small frame that indicates the f-stop and the speed of the shutter that the program will use. At the center, two small yellow and red circles must overly to obtain focus on the subject.
Shutter speeds go from 1/30 to 1/650s, including bulb mode (only at f2.3). Copal shutter closes up to f16, so Rollei reccomends max 400 ISO/ASA films.
There's a hot-shoe flash slot and the camera also includes a self-timer (circa 10s of delay). Under bulb mode, this timer can fire the shutter to a speed of circa 5 seconds.