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 15 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.