APC SmartSlot Triple Chassis UPS card chassis for network administrators provides an additional slot in Smart-UPS, Matrix-UPS, Symmetra Power Array, and Silcon UPSs. Connect the cable of the Expansion Chassis to the RS-232 serial port of the UPS. Then add any one of the following management peripherals to the Expansion Chassis to improve your UPS management system: UPS Interface Expander Card, Environmental Monitoring Card, Out-of-Band Management Card, Relay I/O Card, or Web/SNMP Management Card.