Review on 🚗 Electronic Specialties EZ-Tach 325: The Ultimate Digital Automotive Tachometer for Precision Measurement by Adam Cooper

Just received today. A 9 volt battery is included, which is very nice. I'm trying to set the idle speed on my Honda Accord (the gauges on the dashboard aren't accurate enough below 1000 rpm. It worked! The rpm didn't fluctuate much (maybe +/- 10 rpm at idle) and is more correct or less matching what the tachometer showed (although it's clear that the digital gauges are more accurate - the divisions of the instrument tachometer can really only be read every 100 rpm with reasonable accuracy).