This is a hdcombo enclosure - it was popular around 2004-2006 and it only works for SCPH-7000x type slim ps2's. There is a new thing for those still interested in such a modification called hd-pro. Its maker says it works with newer slim models (a modchip needs to be installed though). See: http://tinyurl.com/3bv2z49
The difference between such a mod and say the usb flash/external drive is that this works with more games and the loading speed is much better. ps2's only have an usb 1.1 connection which limits transfer speed to around 500-700kbyte/sec. That is not too much. The hard drive is much faster as it works with an IDE connection. That also means no sata drives - I never saw a sata-ide adapter that worked with it. Questions can be asked now, though I probably wont be fast to answer. Or at all.
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