It had been 1st released in 1939 for automobiles. It contains the fluid coupling and a few planetary gears. They collectively make 3 ahead and one reverse velocity. There's no clutch for engagement and disengagement through the engine. The copyright which unites all the planetary gears revives the output https://gearbox32974.elbloglibre.com/33763206/gearbox-no-further-a-mystery