This item is used but in good condition. These are used to indicate and manage load and to provide redundant power to devices which only have one PSU / mains socket (you can plug 2x UPS / Power supplies into the PDU and it will switch between the two in the event of a power failure). The Tripp Lite PDUMH20HVAT 10-Way 1U 19-Inch Horizontal Rackmount ATS/Metered PDU provides a redundant power option for single-corded network devices. The dual input cords support separate connection to Primary and Secondary power sources. The Automatic Transfer Switch (ATS) will normally maintain continuous output to all outlets as derived from the primary input cable. If the primary power source becomes unstable or fails altogether, the ATS will switch over to the secondary power source until the primary input is restored and stable. Super-fast switchover between primary and secondary power sources occurs within milliseconds. Featuring 10 outlets with 8 x C13 and 2 x C19 sockets. Provides a redundant power option for critical networking equipment with a single input power cord. 2 digit display reports output power consumption in amps. Front panel LEDs confirm power availability on both input lines. Outlets are factory programmed for sequential turn-on at 250 millisecond intervals when the PDU is first energised. Super-fast switchover between primary and secondary power sources occurs in 2-5 milliseconds. Separate primary & secondary inputs connect to any two compatible power sources.