[Anti-theft alarm] Press and hold button 3 (lock button) for three seconds to enter the pre-arm state, ten seconds to enter the anti-theft monitoring state; enter the anti-theft state, with three-level sensitivity function. Short press button 1 (unlock button) to exit the anti-theft state. (If someone touches or pushes the bike, the electric buzzer will immediately emit a loud and continuous alarm) Light Alert RingtoneThe alert tone can be automatically adjusted from 80 decibels to 130 decibels, especially when driving in the dark, the tone is loud enough to remind other road users to keep a safe distance from others and better protect their own safety. (Button 2 is the default ring button, button 1+ is used for volume up, and button 3 is used for volume down) IPX6 Waterproof & USB Charging Bike Horn High quality IPX6 waterproof electric, can be used in rainy days, extremely convenient and practical for daily use; the electric bicycle horn alarm adopts USB charging (charging method: charging socket, power bank, laptop. ) Simple InstallationEasy to assemble, no tools required, attach the silicone bicycle horn alarm strap to the handle. It can be applied to various bicycles such as mountain bikes/electric scooters/racing cars. (Applicable to bicycle handlebars with a diameter of 22.2-31.8mm) Note: The vibration sound inside the bicycle bell is detected by anti-theft sensitivity, which is a normal phenomenon.< /p> Packing list: 1 * Bike Bell (package without battery) We only sell bike bells, not other items in the picture. Due to the difference between different monitors , the pictures may not reflect the actual color of the item. Due to manual measurement, please allow slight errors in size.