text: own an auto repair shop, No need for a timing light these days but running into some classic car repair and need a timing light. Took a chance... wish I didn't. pulled it out of my box for the first time for an MGB timing check. my old OTC gave up the ghost. I knew the timing was not off just checking it. This light was all over the place no matter where it was up and down the plug wire. Borrowed a friends Harbor Freight light worked perfect timing was dead on and not jumping. Went back and forth between the two lights couldn't believe how messed up this light is. Of course I am past the return window. My advice ...keep looking if your looking for a good light. If your in a bind buy a harbor freight one.