Does that make what it is intended precisely.

I was looking around in my apartment to the media wall to connect another device, without me having to leave this on all the time an additional switch. The Misplaced network cable had all 8 conductors connected to clean the can and the patch panel. So .... there for 100BaseT yes only 4 wires necessary are simple on both ends (socket and patch panel) a T-adapter and there is an additional connection is available (but only to 100BaseT).

The negative ratings in a similar product Anschlussverdoppler Equip Cat. 5e (RJ45 plug - 2x RJ45 jack) I can not confirm. I think here you have not previously possibly misinformed.

It is important to be that two of these products used and that the whole does not replace a switch / router. It uses in order to allow through the same cable line a further connection only (in a normal 100BaseT network) unused 4 wires out. (At the other end of the two ports must of course be connected to a switch / router.)

For the price, the product is great and I can save the operation of another power eater -> Green IT :-)