The Redback A4658 has been designed to provide external power injection to the A4660 Redback Paging Console. This may be required when the A4660 is connected via a long Cat5e/6 cable run, or when two paging consoles are cascaded together and the master unit cannot provide enough power. The power injector can be inserted in the line between the master unit and the paging console, or in the line between the first and second paging consoles.