Why should a company promote themselves using a custom bottle opener key chain? It is because people buy them. No doubt, they are petite, but a bottle opener key chain can serve a dual purpose when used. First, it can be utilized as a key chain to hold keys and keep them safe. Another one is to open the bottles and cans of water and cold drinks. Going on a trip or just to the supermarket can make you feel tired and you might want to grab a can or a bottle of cold drink. At that time, you cannot open these bottles using your teeth. These small things are helpful at such times.