Adjustable tone, volume and sensitivity to meet your needs. Audio and visual alerts will enable you not to miss a bite and makes your fishing easier. Lightweight and water resistant. 2.5mm socket for external . Suitable for day and night time fishing. Fishing Bite Alarm LED Number: 2 LED Color: Blue Battery: 1 * 9V Battery(not included) Screw Diameter: 0.8cm / 0.31in Item Size: 9 x 5 x 4cm / 3.54 x 1.97 x 1.57in Item Weight: 75g / 2.64oz Colour: black Material: ABS Size: 11x4x6cm Package Contents: 1 * Fishing Bite Alarm Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the a little different from the real . The measurement allowed error is +/- 1-3cm.