Low-cost passive PoE base unit for powering passive PoE devices over ethernet. Simply connect your power source to the injector, and then use an ethernet cable to connect the injector to the RouterBOARD device. Helps reducing number of wires that lead up the tower, and in other situations. For using with RouterBOARDS that support 10-28V PoE powering, input needs to be at least 18V to accomodate any losses in cables.