Torque converters from Pik Rite are installed on the input of the right angle gearbox drive to act as a clutch, eliminating shock load between the gearbox and the coupler while still allowing the operation of an automatic transmission. It softly starts the blower versus a harsh, abrupt method that can cause damage to the gearbox and coupler. Packages available for Robuschi and NVE blowers. 800/326-9763; www.pikrite.com.