all it is is a plug with an on/off switch on it that you program to be operated by the power switch on a remote control. so when you press the power switch to put your tv (for example) in standby it automatically turns the plug off at the wall and when you press it again it turns it on.
You can run a 4 way adaptor off it so it will operate more than one thing but they would all be switched by the power button on the same remote control.