A torque converter transfers rotating power through a load. Generally, this takes place of the clutch in an automatic transmission — but, it should be able to multiply the torque.
According to Wikipedia:
The key characteristic of a torque converter is its ability to multiply torque when the output rotational speed is so low as to allow the fluid coming off the curved vanes of the turbine to be deflected off the stator while it is locked against its one-way clutch, thus providing the equivalent of a reduction gear. This is a feature beyond that of the simple fluid coupling, which can match rotational speed but does not multiply torque, thus reduces power.
Some of these devices are also equipped with a “lockup” mechanism which rigidly binds the engine to the transmission when their speeds are nearly equal, to avoid slippage and a resulting loss of efficiency.
Torque Converters are present on many of our leases.