Wheel Disc Brake Lock AntiTheft Security Alarm Universal Motorcycle Scooter Accessory Condition: Item Type: Wheel Disc Brake Lock Color: As Pictures Shown Material: Alloy SteelSize: Approx. 90x80x60mm/3.5x3.1x2.4inBattery: 6pcs Built-in button battery(Model: LR44, Capacity: 150MAh) Application: Suitable for motorcycles and bicycles with brake disc thickness less than 6mm Features: 110db alarm/waterproof/anti-frivolousBattery Replacement: When you hear the low-battery beep or the alarm will stop in less than 10 seconds, which means that the battery will be out of power and you need to replace the battery. Please use the small wrench provided by us to unscrew the four-pin screw at the bottom, remove the casing and replace the battery. Note the positive "+" and negative  "-".