This great-looking GPS speedometer provides accurate speed-over-ground readings and heading information. Can be connected to an existing NMEA 0183 receiver or to a new GPS receiver/antenna (sold separately). With no elements to corrode or break, GPS speedometers are ideal for all speed applications and particularly useful for craft where traditional speed sensors like pitot tubes and paddlewheels do not perform well. Sierra Part #781-684-035P.• Included LCD heading display to show course over ground• Use our GPS antenna (sold separately) or connect to an existing NMEA 0183 GPS device - connectors included• Speed accuracy of +/-1 MPH (once moving)• Heading accuracy of +/-1 degree (once moving)• Ideal for slow speed apps like pontoon boats and for high speed performance boats with pitot tubes• Scratch-resistant domed glass lens• Perimeter lighting for excellent readability at night• U.S. and metric scales Ideal for all speed applications Useful for all types of watercraft | Eclipse GPS Speedometer With LCD Heading Display, 35 MPH