You will never have to worry about replacing your speed sensor gadget again. The Speedometer has a sleek design and cutting-edge technology. With digital stepper motor powered pointers and GPS speed and heading precision of +/- 1 MPH and +/- 1 Degree, respectively. The Speedometer additionally contains a Blue LED that illuminates the dial's perimeter. Ideal replacement for worn-out speed sensor equipment (pitot tube and paddle wheel). WARNING: CA PROPOSITION 65 Key features: Pointers powered by digital stepper motors Ideal alternative for speed sensor devices that degrade over time (pitot tube and paddle wheel) Perfect for slow-moving arteries when pitot tubes are ineffective Connectors made in Germany Anti-fog, scratch-resistant domed glass lens Bezel Made of Stainless Steel A blue LED illuminates the dial's circumference Backlit Illuminated Fire-Orange Tip Pointer An extra GPS antenna is not required 1 second from hot start for ultra-fast satellite acquisition time (TTFF) +/- 1 MPH Speed Accuracy +/- 1 Degree Heading Accuracy Specifications: Brand: FARIA Manufacturer s Part Number: F22010 4" - Hole size: 3.375" (85mm)