Extreme ease of use. Fish ID+ Target Identification marks fish with depth. Structure ID grayscale reveals bottom type and fish attracting structure. Compact unit with full size display; 2-1/16" x 2-1/2" H. Built marine tough and waterproof. Depth capability: 240'. Piranha 1 also available as a compact model. Ultra compact and lightweight. Folds out for quick set-up and folds in for protection during storage and transport. Rugged, protective case with carry handle. Anti-skid rubber bottom keeps the unit solidly in place. Built-in transducer cable wrap keeps your system organized. Uses 8 AA batteries. Suction cup transducer quickly and easily attaches to most boat hull - for use at trolling speeds.