FastMeasure is a small mobile device that quickly and accurately measures distance. FastMeasure is a small mobile device that quickly and accurately measures distance. FastMeasure will measure anywhere you can drive, on-road or off, any place you can use a measuring wheel and a LOT FASTER. -Accuracy within one foot in a mile -Measures in Feet or Meters -Measures at highway speeds -Size approximately 3¿ wide x 1.5" high x 1.75¿ deep -Backlight 8-digit display is 2 1/8" wide x 5/8" tall. The units come complete with everything needed for vehicle installation. The kit includes FM1 Distance Measuring Device, speed sensor, wiring harness, instruction booklet, and 1 year warranty. Installation and calibration of FastMeasure is fast and easy; typically about one hour.