A safety device used on snowmobiles and personal watercraft. One end is attached to the operator's wrist and the other end is plugged into a special switch. When the operator falls off his vehicle, the tether pulls out of the switch causing the engine to die.
TETHER KILL SWITCH
Meaning of TETHER KILL SWITCH in English
English dictionary of automotive terms. Английский словарь автомобильных терминов. 2012