The APC Rack Power Distribution Unit (2G, Metered, ZeroU) is a data-centre/server-rack PDU designed to distribute mains power to multiple rack-mounted devices while giving administrators real-time visibility into power draw. "Metered" means it reports total load (amps/watts) at the unit level so staff can monitor how close a rack is to its power budget — useful for capacity planning and avoiding overloaded circuits, though it doesn't provide per-outlet metering or remote switching the way a "Switched" PDU would. "ZeroU" describes the mounting style: it mounts vertically in the rear of the rack cabinet rather than consuming a horizontal rack unit slot, preserving 1U/2U rack space for servers and networking gear. Rated at 22.0kW capacity on a 32A supply, this is sized for a fairly dense, high-power rack rather than a lightly-loaded one.