This always-active retarder delivers continuous braking pressure to railcars as they enter the unit. The spring design does not require air, hydraulics or electricity to operate. A shim adjusting system simplifies maintenance of the unit.
Adding a hydraulic package turns the AR2 into an operable failsafe unit. In the event of a power failure the spring force closes the retarder making it possible to stop any rolling rail cars, bogies, or wagons