This bicycle rear view mirror is easy to install and it will make your riding safer, the mirror can be closed so it won't increase the resistance of riding. Features: This rearview mirror can be mounted on the handlebars. It can be rotated 360 degrees and you can see the distance of 20-40m behind. Suitable for 16-22mm handlebar of bicycle. Can be used as a bicycle handlebar plug to effectively prevents dust, water, and other foreignobjects from entering the handlebars during daily cycling. Made of fine quality material for long working time and easy to install. Specifications: Color: black Material: nylon+acrylic Rearview mirror diameter: 30mm / 1.2in Item size: 40 * 50mm / 1.6 * 2.0in Item weight: 23g / 0.8ounce Package size: 105 * 64 * 38mm / 4.1 * 2.5 * 1.5in Package weight: 46g / 1.6ounce Packing List: 1 * Handlebar Rearview Mirror