I bought this device because there is only one free ethernet port on the back of my modem and I have a laptop and play station 4 to use with it to connect internet. It arrived and I found something I wasn't expecting. You cannot connect both cables at the same time, even if one of the devices is turned off. For example I plug the device into my modem and use one of the splitters to connect my laptop, it works fine, then I use another splitter for my PS4 and the signal just dies even though my PS4 is off and not controlling internet access.