Some BigClown modules have one or more extra 5-pin sockets allowing to connect a BigClown tag (I2C peripheral in a common form factor). But sometimes this is still not enough or you need to extend the I2C bus with an additional channel.
Tag Module enables to connect up to six extra tags. Every tag has a unique I2C address. Using two independent I2C buses (I2C0 and I2C1) makes it possible to connect two tags of the same address to a single BigClown node.