The CB-35 is a landline telephone, with pulse dialling using a rotary dial. It was manufactured by the PZT (Państwowe Zakłady Tele- i Radiotechniczne) from 1935 until the first years after World War II. It was the first Polish telephone with a Bakelite handset and a centrally located cradle button activated by picking up the receiver. Its design is typical of the telephones of the 1930s.
The main part of the telephone was mounted on a steel base. The housing is made of sheet metal painted black. The telephone was equipped with a metal cradle, and a black plastic and metal dial. On the right side of the housing are sixteen elongated rectangular acoustic slots of the telephone ringer, while on the left are two grommets for the telephone line and the handset. At the bottom are four spacing feet and seven acoustic slots for the ringer. The handset is made of Bakelite. The cable connecting the main body with the handset, which is twisted into plastic insulation, was added later by a user (it is not original). In the unit presented here, the microphone insert was replaced with a later model, the CB 68.
What was exceptional about the CB-35 telephone was the place and time of its production. The dial bears a circle enclosed in a triangle of three lightning bolts – the symbol of the Państwowe Zakłady Tele- i Radiotechniczne. The letters inscribed in the circle, however, are not PZT but FSW, which resulted from reorganisation of the factory by the occupying German authorities. Państwowe Zakłady Tele- i Radiotechniczne was divided into the Fernmeldetechnische Staatswerk Warschau (FSW), which dealt with remote transmission and was subordinated to Deutsche Post Osten, and the DeRuFa Warschau, which was involved in radio-related production and was a subsidiary of Lorenz AG. Production was discontinued in September 1944 when the occupiers blew up the factory buildings