These systems come in 'Ring type' (mounted under or over steering wheel) 'Radial type' (mounted on a hand control) or 'Trigger type' (again mounted on a hand control) Ring throttles are operated by the users thumb pressing a ring of smaller diameter than the steering wheel, Radial throttles are operated by the entire hand rotating a lever and Trigger throttles are operated by a single finger pulling a small lever.

 

 

Electronic Throttles