When my decades old timing light crapped out, and it was time to get a new one, I kind of blundered into this one, and I'm gad I did. I really like this one. In years past there may have been a problem with life span of the strobe light, so timing lights were set up so you had to hold the trigger to make it flash. You just got used to that sort of thing, because there was no alternative, even though it may be a bit awkward to hold the trigger during use. Then I find a lot of modern timing lights have too many unnecessary whistles and bells that make them more complex to use. How much time do you want to spend reading the instruction manual to learn how to use a generally simple tool? Not me, please.

This is the Innova 3555a set-back timing light (or timing light with advance). The first impression with this one is, no battery required, and no digital screen, and no thin film touch pad that would require hand-eye coordination to find the buttons during use. This one is analog in the fine old tradition. There is one button to switch it on, after which it continues to flash without having to hold a trigger. There is just one analog adjustment wheel you can easily work with your thumb while watching the illuminated timing mark, simple one hand operation. Very easy to dial in the zero timing mark while the engine is running, accelerating, and finding the maximum advance speed. Then read the maximum advance from the dial. Or you can wind it down to zero and use it as a standard strobe timing light. The utter simplicity and ease of use is amazing. I give it two thumbs up. No tachometer function.