I have had my cse for a while and have only ever used 1 HDD in it at a time, and don't know where my other screws are for it, or if I even had the in the first place. They are like long screws with a rubber wheel on them which slots into the drive caddy and you screw them in with a thumbscrew if you want too. I have some thumb screws but I need some of the rubber ones. I've tried Amazon and Ebay searches and the Zalman website to no avail. i need to mount more than 1 drive as the cae will house a RAID server for my company