The 90W Redundant Power Supply designed for use with D-Link LAN switches. This power supply connects to a switch to provide redundant backup power to the built-in power supply units inside the switch. This RPS can operate as stand-alone redundant power supply units, but they can also be installed in a DPS-800 or DPS-900 chassis. It comes with their own solid metal case housing and LED status indicators. It can be used as stand-alone power supply unit, or installed in the chassis. As it is independent unit, it can hot-swappable when used with the chassis.