The slide projector (18.5 x 9.0 x 18.5 cm) ASPECTAR 150 A was used to project small-format, framed slides. The trapezoid projector consists of a casing and a lens made of die-cast aluminium with a grey hammer-blow varnish. Ventilation slits have also been incised. A slide feeder can be attached between the front and rear parts of the projector. Without such a feeder, the slides had to be manually inserted. For secure storage, the lens, which was attached to the sheet-metal casing using a bayonet connection, could be detached and inserted into the indentation at the bottom of the device. The ASPECTAR 150 A slide projector was designed in 1957 by Manfred Claus. From 1960 to 1984, it was serially produced by VEB Kamera- und Kinowerke Dresden (resulting in a total of approx. half a million devices) and sold under the brand name Pentacon. The projector’s case includes the characteristic Pentacon logo with the Ernemannturm building.