If, like me, you have a home PC and work laptop, but want to use the big screen for your laptop, then this is the best way forwards. You simply plug your monitor into the input socket (clearly marked) and then connent one cable to the PC and another to the laptop, plugging them into this box at the other end, you then can switch between them at ease. Its a definate click to change buttons, and some monitors may need turning on and off if they have modern power savers and you have just switched over. The other thhng to do is make sure you buy two extra cables and measure the length you want!. I wanted very little cable so bought a pack of two 0.5m cables.
This box is female - all the plugs have holes, not prongs! Make sure you get the right types of cable and switch for your monitor, most standard VGA monitors need male to male cables.