As you may know, the 7 address length I2C bus allows up to 128 I2C devices to access. At present, there are over 80 Grove I2C modules in Seeed, however, normally only 1 or 2 Grove I2C connectors are available on the Seeeduino Board or the Grove Base Shield. What if we need to use multi Grove I2C modules in the system? The answer is Grove - I2C Hub (6 Port). 

There are 6 Grove connectors in this hub, one input, five output, or you can even connect one hub with another, so that more devices can be plugged in. Not only I2C but also can be used to control several synchronous change devices(like LEDs).