Best for both amateurs & professionals. Detects both fish location and depth in fresh and salt water. Use it in one of the following ways: With Rod and Line / Roach Pole With bait boats Features: Display Fish Icon and Live-Update Water Bottom Contour Detects and displays big and small fish or groups of big and small fish Resist interference from grass when used in lake Adjustable chart speed, sensitivity level, depth range, Sonar sensitivity setting Audible fish and depth alarm Zoom at specified depth Indicator for battery and Signal for Wireless Sensor Simulation mode Built-in memory Sensor auto switch off when not in water CE & RoHS approved Specifications: Display: Adjustable High-contrast Dot matrix FSTN LCD 128(V) x 64(H) Display Size: 41 x 48mm Backlight: White LED with on/off option Frequency: 433 MHz wireless, 125 kHz sonar Wireless Sensor Coverage: 90° beam angle Depth Range: 45m Wireless operational range: 120 meters Water Temperature: °C/°F Units: meter or feet Built-in memory stores sonar setting when the unit is turned off Operating Temp.: 14~122°F (-10~50°C) Storage Temp.: -4~158°F (-20~70°C) Language: English (default), Russian and Deutsch Battery life of Wireless Sensor: up to 550 hours in water usage IPX4 Water Resistant Design / Level-4 (spray-water-proof) Power Supply main unit: 4 x AAA Alkaline Battery (not included) wireless sensor: 1 x CR-2032 Button Battery (included) Size: approx. 136 x 74 x 30mm Weight: approx. 160g (main unit only) Set Includes: 1 x Professional Black Version Wireless Fish Finder 1 x Wireless Sensor 1 x External Antenna 1 x Neck Strap 1 x 3V CR2032 Button Battery 1 x English User Manual