Review on Ethernet Splitter Canbuau Internet Connector by Rodney Bullock

They MUST be used in pairs. The 1st splitter takes two internet cables (each with 4 of the 8 wires in the cable), combines both cables to use all 8 wires in ONE cable, then the 2nd splitter shifts the two combined signals on one cable back into two cables. The pair is used ONLY to save running a second cable. If you want to connect more than one device to your router using the SAME CONNECTION, you need a hub, NOT this one. Sometimes only one cable runs through the wall and you need two cables. This uses 4 unused wires in that cable in the wall. You cannot use this if you need a POE cable as POE uses 6 out of 8 wires.