We now offer two different models of our Self-Powered Timing Lights for 2 or 4 cycle applications. Both feature the desirable one-wire inductive lead design. They operate on two "D" cell batteries, so there's no need to connect them to the vehicle's battery. Both models are magneto compatible and also incorporate a bright xenon flash tube for use in sunny daylight conditions. Our standard model is usable to about 5000 rpm, while our Pro Model can operate beyond the 10,000RPM range. Our heavy-duty pro model features a burn proof aluminum pick-up with a high temp fire sleeve over the lead cable.