The horn is easy to use, just quickly squeeze the rubber ball and release it to generate the sound. The horn is sharp and loud, easy to draw the attention of the pedestrian and avoid the dangerous situation Made of high quality aluminum alloy material and advanced rubber, waterproof and rustproof. Light weight and durable. Easy installation, the mounting part fits for universal with 22.2mm diameter. Dimensions: 180 mm x 75 mm x 65 mm (7 in x 3 in x 2.6 in), Mount: dia. 22.2 mm.