What PS2 is this?

Sorry to sound like a gaming dumb-dumb, but I have never seen this slim model Playstation 2 before. Here's two different slim models for you to compare:

Left: The mysterious new model. Right: The original w/ box.

I mean, it looks like the original slim model Playstation 2 that I have, but there's some irregularities. For instance, there's no shiny strip of plastic next to the disc tray, nor fans on the front next to the USB drive, and there was three plastic stripes on the edge, not just one.

See what I'm talking about though? I mean, I guess it's not a big deal since Sony's primary focus is now the PS3 (which not all models supprt PS2 games, by the way). But all I want to know is where was I when they made the case switch, and are their any other differences?

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