A Detailed Look
The FSP Twins 500W redundant power supply enclosure/frame is painted satin black and measures 190mm (7.4””) deep. The power supply comes with a basic assortment of flat ribbon-style fixed cables (see specs section for details).
Removing the cover exposes the two modular power supplies. The modules slide into the main chassis/frame from the rear and plug into card-edge-connectors at the front. A mechanical latch holds the modules in place.
Each modular power supply is cooled with a 40mm fan mounted on the front (Protechnic Electric MGT4012ZB-W28) rated at 0.49A at 12 VDC and use double ball bearings, which is good as these little fans can easily spin in excess of 10,000 rpm. Unfortunately, these small diameter fans are the common choice for use in server-style power supplies because of space constraints. The obvious down side is the noise they generate.