It is the most common and a very simple one. It is enough to push the lever, which hits the discs inside the bell housing (aluminum / steel / copper). Normally it is installed on inexpensive models on the handlebars, using a bracket and a screw. Its advantages are various designs and a quite affordable price. However, they have quiet, almost inaudible sound, to which only pedestrians will react. Also mechanical bells don’t work properly in the rain and frost and rattle heavily on rough roads.
The principle of operation is simple - when you press on the klaxon, the air passes through the "squeaker" and produces the sound vibrations. A flare is used to enhance the effect. Recently, manufacturers have installed pneumoclaxon on some bicycles. This signal is powered by a compressed air cylinder. A distinctive feature is a loud sound, but requires certain operating skills.
Advantages: lightweight, small size, the ability to customize different sounds - from sirens to melodies (changed by pressing a button), volume control, wide range of colors. Comes with plastic fasteners. Installed quickly and easily. Usually powered by two batteries or a rechargeable battery.
So, cyclists have plenty to choose from, depending on style, preferences and the budget.
Main selection criteria:
For the horn, the material from which it is made (metal / plastic) is also important.
Fixing method (screw, with a clamp, with a set of elastic rings). Pay attention to this point in advance.
Aesthetic appearance. A variety of colors and shapes to suit every taste.