This Oval Track Tach Features Single recordings of up to 10 minutes in Memory. Choose from Half or full speed Playback. Lap marker provides accurate lap time for multi-lap recording. A single stage shift light connection is provided for the optional 74836 Quick-lite. Highest rpm can be recalled in Playback. Printer Interface allows recording to be printed without a computer for analysis and hard copy storage. Operates on 4, 6, or 8 cyl. engines with std., electronic, and most high performance racing ignitions with 12 volt power.