The Triplett PoE-Bug is a simple plug and play tool that allows the installer to test RJ45 ports and correctly identify Power Over Ethernet without the risk of damaging expensive equipment. It can detect 802.3af, 802.3at and non-standard DC power from 5 to 57VDC . It also indicates if PoE is End-Span or Mid-Span with the use of easy to read bright LEDs. No batteries required, self powered by PoE. 1 year warranty.