They were specially designed for disabled drivers and were distributed in the USSR free or at a large discount through the Soviet Union's social welfare system, and were not officially sold to non-disabled people.

It was powered by a 346 cc single-cylinder two-stroke engine, giving 10 hp (7 kW) and a top speed of 55 km/h (34 mph).

The S-3D, produced between 1970 and 1997, was a twin-seat, four-wheeled cyclecar, 2.6 metres (102.4 in) in length, but rather heavy (≈500 kg) due to all-steel body.

In the USSR, the model was commonly known as a "motor-wheelchair" (Russian: инвалидка, invalidka) because they were only leased via the social care system to disabled people for five years without permission to sell (in a similar way to the British Invacars, made by AC, Thundersley and Tippen).

Like the Invacars, not all invalidkas were scrapped, because some of their disabled lessees managed to register them as their private property.