Humminbird  AS GPS HS Precision GPS Receiver with Heading Sensor, Standard with 360 Imaging When used with 360 Imaging, provides the ability to mark accurate waypoints anywhere on the screen Series: 1100, 900, 800, 700 fast position fixes accurate within 2.5 meters Provides more accurate position fixes than the industry standard GPS 3.25 inch diameter, 1.5 inch high and comes with 20' cable 1 inch-14 thread count stem mountable with an optional atenna stem