TwinScan Flometer Instruments set the standard for easy readability in the least possible space. The TwinScan Flometer contains port and starboard meters which reference each other. In a quick glance you see nonmatching pointers that signal possible trouble. Potentially dangerous and costly engine problems that might go unnoticed on conventional instrument panels are highlighted on a TwinScan panel. A patented miniature design is the first to allow two meters to fit the industry standard 33/8" diameter holes. The tachometer/speedometer/MPG/sync indicator takes a NMEA 0183 speed signal from your GPS or Loran and fuel flow from the TwinScan GPH instrument to digitally display speed over ground, fuel efficiency, or RPM difference between port and starboard engines. All instruments are constructed of a corrosion-free stainless steel bezel and molded acetal cases. Internally illuminated pointers provide exceptionally effective night readability. Available in black and white with red pointers. One-year warranty.