Specification : 1. Measure Units: Meters / Feet 2. Display: LCD 3. Backlighting: LED 4. 4.6cm diameter Round transducer sensor 5. Depth Range : Max: 100m (328ft) ; Min: 0.9m (3ft) 6. Sensor Beam Angle: 45 degrees 7. Display the nature or circumstance of bottom of Sea (i.e. grass, rock and sand) 8. Operating Temperature is from -10°C to 45°C (14°F to 113°F) 9. Uses 4 x AAA batteries (not included) Package Included : 1. Fish Finder Display 2. Sonar Sensor (Transducer) with 25ft cable 3. Removable Transducer Float with Rubber Stopper 4.Transducer Side-Scan Adapter 5. Stainless Bolt and Wing Nut 6.Neck Strap 7.Operation Manual How to use the Sonar Sensor: