One (also labelled "L"): Restricts the transmission to 1st gear only, also called a "minimal gear". This is beneficial when a big torque is required at the wheels (such as, when accelerating up a steep incline); nevertheless use at increased speeds can operate the motor at an too much speed, https://gearbox-auto08528.wizzardsblog.com/34090221/an-unbiased-view-of-gearbox-auto