100/1000M RJ45 Ethernet Cat5e/6 surge protector with PoE support. It simply installs in-line on an RJ45 Cat5e/6 cable. The arrestor has two RJ45 female jacks, so the in-line installation is a very easy and straight forward. It protects any Ethernet devices like switches, routers, laptops/PCs,IP Camera etc from damaging surges caused by static electricity. Moreover, because of PoE feature it ALLOWS PoE enabled devices to remain powered while still protected against damaging strikes or voltage spikes. IMPORTANT Two things are crucial and should NOT be missed when using the Ethernet surge protector: correct positioning: IN jack on the unprotected part of cable and OUT jack on the protected side of cable. Reversed installation will still allow network traffic and operation but there will be surge protection at all! proper grounding: please note the yellow/green ground wire. This wire must be connected to proper electrical ground in the building. Ask a qualified electrician about such grounding or search the Internet for information. Without proper grounding the surge protector will be unable to drain away the excess voltage and will be ineffective! Features of POE1000M surge protector Fast energy absorption on over-voltage Low resistance and minimal capacitance - minimal influence on data link Easy in-line installation: two RJ45 female connectors Colour:As shown Material:plastic Package Contents: 4 x POE Network IP LAN Surge Protection Device