Platinum 4" Speedometer - 50 MPH (Mechanical)Faria Beede’s Platinum Series Instruments feature spun aluminum gauge dials with custom graphics and a polished stainless steel bezel providing a rugged, elegant look.  All Platinum Series gauges feature Faria's revolutionary domed glass Fog-Resistant lens. These lenses shed condensation and resists scratching and other types of fouling common in the marine environment.  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:Domed Glass Anti-fog, Scratch Resistant LensStainless Steel BezelBlue LED Illuminating around the Perimeter of the DialIlluminated Backlit Fire-Orange Tip PointerFactory P/N SE9864