Alarm system for bicycles. Automatic alarm activation via motion sensor. Sensitivity adjustable. Volume of 120 dB. Code can be set with 3 digits. Includes batteries. Mounts to the seat post. Thanks to M-Wave, there is now an alarm system not only for your home but also for your bicycle. The "Watchdog" sounds at a volume of 120 dB as soon as the motion sensor is triggered. You can decide on the sensitivity of the device yourself. The alarm code can also be set by you with 3 digits. Simply attach the included holder for tube diameters of 25 to 30 mm to your bicycle, insert the included batteries, and you're ready to go.