The HELIX 15 CHIRP MSI+ GPS G4N CHO features a 15.4'' display, MEGA Side Imaging+, MEGA Down Imaging+, Dual Spectrum CHIRP Sonar and internal GPS with Humminbird Basemap. As with all HELIX G4N models, this HELIX 12 includes standard features such as AutoChart Live, Wi-Fi and NMEA 2000, in addition to Bluetooth and Ethernet networking for compatibility with the One-Boat Network family of products from Humminbird, Minn Kota and Cannon. This CHO (Control Head Only) model allows you to pick the right accessory transducer for your needs, including compatibility with Minn Kota Built-in MEGA Imaging trolling motors.;Features:Control Head Only Model: This model does not include a transducer. This CHO model is a great choice for those looking to connect to connect to Built-in MEGA Imaging on Minn Kota trolling motors, accessory transducer options like MEGA 360 Imaging, or share sonar data from an existing Humminbird Ethernet network.;Keypad control: Master HELIX at the touch of a button. Access the preloaded views from the user-friendly menu system, operated by soft key controls that allow you to reliably operate your fish finder in any condition.MEGA Down Imaging+: Get unprecedented underwater clarity with Down Imaging coverage down to 200 feet below your boat.;Dual Spectrum CHIRP sonar: Before you cast, know what's down there thanks to highly-detailed fish arches and a clear view of fish-holding structure and the bottom.Internal GPS and Humminbird Basemap: Our enhanced basemap provides you with a clear view of underwater terrain and surrounding points of interest so you can fish and navigate with total confidence. Identify buoys, day markers, hazards, marinas, contours, depth markers and much, much more. Includes charts of more than 10,000 lakes, plus coastal coverage for the continental U.S.