The Intellinet 780131 PoE+ Tester is a small plug-and-play tool for network and CCTV installers that confirms whether a cable run or switch port is delivering Power over Ethernet before you connect expensive equipment. It detects both IEEE 802.3af (PoE) and IEEE 802.3at (PoE+) power, and its LEDs indicate whether the power sourcing equipment is Endspan (power on pins 1/2 and 3/6, typical of PoE switches) or Midspan (pins 4/5 and 7/8, typical of injectors). Just connect it inline using its RJ45 port and the attached 10cm RJ45 lead - no batteries or setup. It's ideal when installing IP cameras, wireless access points and VoIP phones, or troubleshooting why a PoE device won't power up. Note this is a PoE detector, not a cable continuity/wiremap tester. The pocket-size unit measures 27.94 x 33.02 x 68.58mm and comes with the 10cm cable and an instruction manual, backed by Intellinet's warranty (2 years per Esquire).