Generic Portable Dot Matrix Sonar Fish Finder 1) Dot matrix display 2) Depth readout from 2.0-240ft(0.6-73m) 3) Fish/depth alarm 4) Selectable sensitivity 5) Water temperature detection 6) Water bottom contour indicator 7) Zoom on/off 8) Removable transducer float 9) Sonar Alarms: Fish /Shallow Specification 1) Display Resolution: 128x64 (HxW) Pixels 2) Sonar Frequency:125KHZ 3) Display: FSTN/Positive 4) Backlighting: white led 5) Power: 4xAAA batteries(not included) 6) Mesure unit: feet/meter 7) Sensor beam angle: 45 degree 8) Depth range max: 73m 9) Depth range min: 0.6m 10) Operating temperature: -4H-158H(-20-70) 11) Size: 130x75x25mm