Mercury - Tachometer 7000 RPM SmartCraft Analog Gauge White Face 110 mm 79-8M0052877. Overview. The Mercury Tachometer (79-8M0052877) provides clear, accurate RPM readings up to 7000 RPM, giving you the data you need to run your boat efficiently and confidently. The white face, black numerals, and glass lens make it bright and easy to read in any light, while the large 110 mm (4-3/8") display gives it a bold, professional look. Designed to work with SmartCraft-capable systems, this tachometer de