This tool has been indispensable to dialing in my vintage motorcycle. Using on my 1979 Yamaha XS650 to check RPM, Dwell, and Timing. Instructions and telephone tech support are horrible though. Called tech support to ask how to check dwell on motorcycle and they said it is not possible. Fortunately, they were wrong. You hook-up the green lead to your points terminal and PRESTO! Provides dwell reading!Green lead is a bit big and bulky though. I connected a smaller alligator-clip lead to their bulky green lead for a more precise connection. Improvement would be to display Dwell out to another decimal place (1/10th).I haven't used 1 yet personally but the guy I have gotten it for as a gift loves it, had to read the instructions a few times and watch the videos but once he unstood the instructions it is easy. I just wish I had gotten 1 for myself. Now they're not on sale anymore and I am just now hearing from him since he is back in town.This is a great tool! Having the dial in advance along with the tachometer allows you to measure the advance at any given RPM. You simply hold the throttle to a given RPM and then press the up or down arrow to change the advance, when the timing mark on the pulley reaches zero, that is your advance at that RPM. I checked mine in 500 RPM increments and wrote down the readings, that gives me the advance curve.Don't forget that for a 4 cylinder engine, you have to divide the dwell by 1/2.Accurate ready you useEasy to use, works greateasy to use. I needed the advanced feature because i only have one mark to show TDC. so i was able to use that and set my timing with this light. I also like the RPM.Great timing light with all the bells & whistles, should of got this type years ago. Easy to use, check timing without having to chase the mark around with advance built in to the light. Nice plus is that it shows live point dwell as well as RPM. Innova in my experience makes nice tools at a good price. Definitely would recommend.I love this timing light. It comes with a solid case and has all the functions I need in a single device. Probably not that useful for a modern car, but great for a classic. Timing, tachometer, dwell and voltage are the critical parameters for me. So far, I have not needed tech support. The manual is available on line and seemed a little unclear/intimidating at first, but was easy after I got used to the function keys.I purchased primarily to get an accurate tachometer based on measured spark and dwell was a plus, but got more features too. Quite satisfied.A well made piece of kit that will likely outlast me and the storage case will prevent accidental damage. The adjustable head angle is very useful for tight engine bays. Being able to set the required advance makes using it a doddle as tdc marks are always easier to identify, no longer will I have to carefully count barely legible timing marks!Bought this to set the dwell and timing on a classic mini. What a superb tool so easy to use and the quality is great. I may be wrong but it looks identical to the snap on version. It also comes in a very nice blown case which is the icing on the cake. Buy it you will be pleased.Too complicated still not worked out to useExcellent gun, easy to use with various functions. For dialling in advance and checking points dwell angle—- perfect. Recommended.A very good piece of kit. Has no trouble with any ignition system I have used it on so far, unlike my SnapOn, and the display is clear and well designed.I would recommend anyone to get this.