Kronos 4″ Speedometer – 60MPH (Mechanical)Polished Stainless Steel bezel, flat glass lens, perimeter lighted spun aluminum dial with Gold and Black graphics. Gold increments and Logo on dial are Embossed. All instruments include two piece Newport pointer with White hub.Electronic speedometers operate by capturing pulses produced by a sensor. the pulses are then electronically converted to a speed reading very much like a tachometer converts ignition pulses to RPM.Pitot tube type speedometers operate by pressure from the water being forced into the pitot tube. This pressure is then transmitted through flexible tubing to the bourdon tube movement inside the speedometer head where it is converted into a speed reading by the movement mechanism.Pitot tube sold separately.4″ – Hole Size: 3.375″ (85mm)Specifications:Flat Scratch Resistant LensPolished Stainless Steel bezelLED Illuminating around the Perimeter of the DialNewport style White PointerFactory P/N SE945*Sold as an Individual**Gauge Cover not IncludedThis product may not be returned to the original point of purchase. Please contact the manufacturer directly with any issues or concerns.