The APC NetShelter SX is a 48U server rack enclosure, 750mm wide by 1200mm deep with side panels included, built to house dense server, storage and networking equipment in a data centre or comms room. Its 48U height gives significant vertical capacity for a full stack of servers, switches and patch panels, while the wider/deeper 750x1200mm footprint provides extra cable-management and airflow space compared to a standard-depth rack — useful for deep servers, PDUs and cable-heavy switch installations. As a rack enclosure it's physical infrastructure rather than active IT equipment, bought by organisations building out or expanding a server room.