Several series of this car were produced in the Poprad railcar building company, first between 1967 and 1970, then in 1977-1987 with partial innovations to the design. Several thousand cars of this type were built overall; a part of the production was exported. The last series of the innovated design was built in the Studénka railcar building company between 1989 and 1994.
The undercarriage of the car is welded from rolled and shaped steel profiles while the body is welded from rolled, pressed profiles and metal sheets. The hopper loads from the open top, through an 8400x1600 mm opening. It has four 1600 mm wide dump doors located 380 mm above the rail head. The hatches allow tripping into the rail, low-level bins, or to a belt conveyor.
The unloading mechanism consists of the door controls, rotary segment doors, flaps for flow direction of the ballast being unloaded, and the chutes. The manual control lever at the car platform is connected via rods and drawbars to two chute doors with identical function on each side of the car.
Car unloading may be performed into the track on both or one side, outside the track on both or one side, or one side into the track and the other outside the track simultaneously. The car may also be emptied while travelling at low speeds; the controls may be used to pause the operation.
Basic technical data: Car length over buffers: 12740 mm, Maximum car width: 3100 mm, Maximum car height: 4000 mm, Distance between bogie axles: 2000 mm, Distance between bogie pivots: 7500 mm, Cargo volume capacity: 38 cubic metres, Cargo weight capacity: 47 tonnes.
