From learn.makeblock.com - December 13, 2016 3:51 PM
The Me RJ25 Adapter module converts the standard RJ25 port into six pins (VCC, GND, S1, S2, SDA, and SCL) so that they can be easily drawn out from MakeBlock port in compatible with electronic modules from other manufacturers, such as temperature sensor and servo module. This module should be connected to the ports with yellow, blue, or black ID on Makeblock Orion.