Package Include:1 x Bicycle Horn4 x Button Cell2 x Belts1 x English ManualSpecifications:Features:- One key control, easily install and compatible with all bikes including road bikes- Security surveillance: if the bicycle is shaking, the horn will sound an alarm for 15 seconds- Password change function- Waterproof, ultra-loud & clear sound- Easy and safe to use when brakingModel: SD-603Material: PlasticColor: BlackSize: 6cm(Length)， 4.2cm( Diameter)Length of Cable： 18cmBattery: LR444 (Included)Functions:- Loud Alarm- One Key Control- Password Controlled- Vibration Alarm- Password Change- Waterproof