Feature: 1. Applicable Range: Can display water depth, approximate location and size of fish, short and tall weeds, sand and rocks at the bottom, etc. You can use the detector on kayaks with speeds below 5 miles per hour. 2. Portable Design: Equipped with a neck strap, you can wear it around your neck when busy on a kayak or put it in your fishing gear box, suitable for kayak fishing, offshore fishing, or ice fishing. 3. Battery Powered: The underwater detector is powered by 4 AAA batteries (not included) and can be continuously used for 4‑5 hours, convenient to use, and can be used in fresh water and seawater. 4. With Sonar Sensor: This fish detector uses sonar sensor to detect water depth and fish position, sonar frequency is 200kHz, with 45 degree sensor radiation angle, and has a wide detection range. 5. Multiple Function: Throw the sensor into the water and turn on the display device, to display the depth of the water and fish, with 5 sensitivity, power saving and backlight mode, fish alarm, and save settings. Specification: Item Type: Ultrasonic Detector Material: ABS Display Method: LCD Display Screen Backlight Mode: Highlight LED Power Requirement: 4 x AAA Dry Battery (not included) Measurement Unit: Inch, Meter Sensor Radiation Angle: 45 Degrees Maximum Measurement Depth: Approx. 100 meter / 328.1ft Minimum Measurement Depth: Approx. 0.6 meter / 2ft Working Temperature: -20℃-70℃ Sonar Frequency: 200kHz Detection Line Length: Approx. 10m / 32.8ft. Package List: 1 x Detector1 x Hand Rope1 x Support1 x Screw1 x User Manual Note: There is a slight error in size.