 Hi, I'm Andy from readle and in this video we're going to be talking about cards as part of an intercom system Now cards make up a very important building block of the intercom and that is an important phrase here building block Cards can be put into an intercom frame and obviously taken out and they can be replaced by audio cards That work with a different format It also means that if you finished using one format in a system You can take that card out and put it into another system by using these building blocks Interchangeably it means that you can customize the intercom system to suit your needs