The APC Smart-UPS RT SURT15KRMXLi is a 15kVA double-conversion online UPS in a 12U rack-mount chassis, the smaller sibling of APC's SURT20KRMXLi. It ships with the AP9619 Network Management Card pre-installed in its smart slot, adding SNMP/web-based remote monitoring plus environmental sensor input, and includes a cooling fan for sustained load. Like the rest of the Smart-UPS RT range it supports additional SURT192RMXLBP2 external battery packs to extend runtime beyond the internal batteries. Double-conversion online topology gives continuous, regulated power with no transfer-time gap, making it suitable for protecting server racks and networking equipment against both outages and poor-quality mains power.