Humminbird 678c HD DI Xtreme Depth fishfinder features a 480H x 640VH 5" color display with backlight, DualBeamPLUS sonar with 4000 Watts PTP power output. Maximize your angling experience with the Humminbird 678c HD DI fishfinder. Sonar Only - Xtreme Depth. 409420-1. The 600 Series when screen size isn"t everything but advanced features are a must, the smart money is on the 600 Series. With an unbelievably clear, HD display, this incredible value delivers more options than you can shake a rod and reel at. Choose from Imaging Sonar, SwitchFire Sonar and GPS cartography. Get it on the water, and this bad boy is tough to beat. Because you don"t need to be a big fish, to put up a big fight. Model: 409420-1