Name: 35mm bicycle flick bell material: aluminium alloy+plastic how to use: press switch down good sound ... easy install Name: 35mm bicycle bell,flick bellmaterial: aluminium alloy+plasticcolor: red,aluminium plain,golden,black,etc.how to use:press switch ... according to QB/T 1723-1993<>,below is certificate: sell aluminium alloy color bicycle bell mountain bike cell,mini flick bell