Review on MASO Car Spark Plugs Engine Digital Tach Meter – Motorcycle Electronic Tachometer with Timer Gauge and Digital Display, Ideal for Small Gasoline Engines (with Clip) by Jay Elgouhari

Bought because it came with an alligator clip for reading from a distance rather than directly over the spark plug. Not sure if it's worth much as the wire just sits in a plastic sleeve and falls out too easily. Cannot "turn on". However, it is legible. The real problem is that the instructions say you have to press the "mode" button to select the type of engine you are controlling for RPM i.e. 2-stroke, 4-stroke, 2-cylinder etc. It there is no "mode" button! Just the "RST" button (which they also refer to). it doesn't seem to do anything. I have no idea if the device is reading my 4-stroke engine accurately, or what engine type it defaults to (2-stroke, 4-cylinder, multi-cylinder, or if it can even read different engine classes as advertised). In addition, the instructions state that it turns off to save battery power. It never turns off. The battery is also not replaceable as it is sealed. There seem to be better ones out there and at the same or lower price than this one. I'm sending mine back.