The TP-DCDC-4856G-VHP is a very high power DC to DC converter / passive POE inserter designed for Ubiquiti airFiber antennas and also various outdoor PTZ security cameras.The DCDC converter supplies 70W passive POE power on all 8 Ethernet wires.They have two isolated inputs for connecting 2 power sources, like a primary and backup power source. They have various protections for surge, short circuit and overload. The input and output are isolated.