Power Over Ethernet Passive PoE Adapter Injector+Splitter Kit PoE Cable Black UK
Since standard Ethernet needs only 2 of the 4 pairs in a CAT-5 cable, 2 pairs are unused. Passive POE uses pins 4/5 for plus power, and 7/8 for ground. This kit has 2 pieces, an Injector and a Splitter.