Fishes and bottom contour readout: This fish finder portable detects and displays water depth, approximate fish location, short and tall weeds, sand and rocks on bottom. Fish finder portable design gives you another option to hang it around neck. The kayak fish finder suits for variety fishes fishing environments: It can be used for off shore fishing, kayak fishing, ice fishing, lake fishing, sea fishing and so on. You can also use handheld fish finder on the moving kayak with speed below 5mph. Depth readout: The fish finder portable detector range is in a 45cone underwater. The detection of depth range is from 3ft(1m) to 328ft (100m) below fishing sonar transducer. The water depth can be shown either in feet or meter. The fishing sonar sensor is with 25 ft cable and removable transducer float. Small portable fish finder with powerful functions: 5 modes sensitivity options; battery save mode; backlight mode; fish and fish school alarm. Normally fishing depth finder supports 4-5 hours continuous working with brand new batteries. Open battery save mode can be working even longer.