A semi-automatic transmission (SAT) (also known as a clutchless manual transmission, automated manual transmission, flappy-paddle gearbox, or paddle-shift gearbox) is an automobile transmission that does not change gears automatically, but rather facilitates manual gear changes by dispensing with the need to press a clutch pedal at the same time as changing gears.
It uses electronic sensors, pneumatics, processors and actuators to execute gear shifts on input from the driver or by a computer. This removes the need for a clutch pedal which the driver otherwise needs to depress before making a gear change, since the clutch itself is actuated by electronic equipment which can synchronise the timing and torque required to make quick, smooth gear shifts.
The system was designed by automobile manufacturers to provide a better driving experience through fast overtaking maneuvers on highways. With Pinalloy Paddle Shifter Extensions, you could use a system with a conventional gearchange but without the need for manual clutch operation.