Traditional incandescent lighting illuminates the front of the dial 12 and 16 volt compatible, well-suited with nearly every street or performance car electrical system Equus' street performance air-core electric tachometers provide quick and accurate readings with a needle so responsive it can go from 0 - full scale in 333 milliseconds Compatible with most 4, 6, and 8 cylinder engines (2 - 4 pulse per revolution ignition signals) with points, electronic, and most 12V high-performance racing ignitions Optimize use of your engine's power band and improve vehicle run performance and driver gear changes with a rapid response, high visibility user-programmable shift light Fit type: Universal Fit