Follwing customer request, we came up with this useful optional air/fuel ratio function. This instrument has a large graph bar and RPM digits, which makes it very easy to read, even at high speed. The adjustable scale for 10 000, 15 000 or 20 000 RPM allows this meter to adapt to almost any type of engine. Other than its RPM and 2 temperature readings, this meter also features voltage and clock functions. It's programmable shift light and temperature warning lights will help youmonitor your engine and make it the perfect racing tool!