APC Power Distribution Unit 24 AC Outlets Rack Mountable 0U Black AP7553 Features Resettable circuit breakers – enables a quick recovery from overload events Toolless Rack Mounting Capabilities – Server cases do not require additional tools to mount into NetShelter Enclosures, which allows the users to quickly and easily mount units in the rear of the enclosure. Vertical Mounting Capabilities – Easily mounts vertically in racks or enclosures and occupies zero U of valuable rack space, which allows more equipment in the rack. Units that mount vertically are optimized to fit in a NetShelter enclosures.