Internal 400w power supply unit for all models of mirror door PowerMac G4 as well as the 2002ED Quicksilver, it is fully interchangeable with the 360w PSU. See below for details.

Manufacturers ID: ACBEL API1PC36, ID292, ID290
Samsung PSCF401601B (C)

Please note: the 360W power supply was originally sold as an energy efficient option in the Mirror Door machines. It was later found that there was a higher failure rate of these units, so they upped the capacity to 400W. It was less energy efficient, but had lower failure rates. They are fully interchangeable, just a more stable option long term.