i was looking at a spare dead 2.5" sata hard drive (the one that came from a old and dead PS3 I salvaged some stuff from). the hard drive does attach to the caddy using small fine threaded PC hardware screws that are used to mount hard drives and DVD or CD rom drives inside PC cases. most PC shops should sell them, you may want to invest in a PC toolkit that has screwdrivers made to work with those teeny screws
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