100dB Electric Bike Horn - Rechargeable Waterproof Bicycle Bell 4 Sounds;

Notice before buying:
Please notice that this is a bicycle siren alarm, it sounds more like a siren,
sounds is "chirp", "chirp".If battery is normal, the sound is loud enough.

This device is simple to install.
The mount is easy to install onto a standard bike handlebar and have it secured to the point it won't move.
The cable wire is long enough to position near the left or right handle, just out of the way of accidentally pressures,
but still close enough so you can slide your thumb and activate the horn.
The horn is loud enough to get anyone who doesn't have music blaring in their ears, deaf or a couple of other things that
would stop them from hearing just about anything in their environment, attention.
It emits a fairly loud and piercing sound that will turn heads in close to moderate proximity.
To activate the alarm, you just hold down the "0" button for a few seconds.
After that, if there is even a slight movement, the siren will sound alarm.
It's moderately loud--certainly loud enough to scare off a burglar.

Troubleshooting:
Sound is not loud as usual: Low battery, please change a new one;
False alarm: Bicycles is not stand stably or other things make it alarm;
Abnormal sound when shaking the item: It is normal sound, just ignore it.

Specification
Mounting-Pipe Diameter: Approx. 2.5cm
Default Password: 0000
Power Supply: 4 X AG13 Button Battery (includes in Package)
Material: Plastic
Size: 6 * 4 cm (Length * Diameter)
Color: Black
Weight: 100g

Package Content
1 X Alarm Lock (with Builted-in Battery)
2 X Mounting Belt