Blue Red Bicycle Bike 4 Tones Electronic Light Siren Beeper Horn Bell by Hwydo Bicycle Bike 4 Tones Trumpet Electronic Siren Beeper Horn 1. 5.11*2.36*2.16"(13*6*5.5cm) 2. Powered by 2*AA batteries(not include in this listing) 3. Fix to the handle bar of the bicycle easily 4. With loud siren sound