Specification </br> Material: alloy top, plastic base /<br> Dome Size: 55mm </br> Fits 22.2mm Bars </br> Features</br> </br> Fits handlebars with 22.2 millimeter diameter</br> Easy to install, just tighten the screw on the handlebar with a screwdriver</br> Traditional design bike bell with thumb-activated ring-ring sound</br> Announce your presence to motorists, fellow cyclists, pedestrians, or other bike users with the loud crisp ring</br> Made with alloy and tough plastic materials for durable use