universal 3.5 to 2.5 bracket (compatible for server hot swap caddy)
There are a number of 2.5" to 3.5" drive brackets on thingiverse, but only one seem to be for hot-swap server bays with drive caddies (because the others don't mount the 2.5" drive in the required position).
That may be because you can just screw your SSD into the corner of the caddy with two screws, but if you want it to be a tiny bit more secure, just print this out and screw it to the SSD drive (and then to the caddy). And in some old server there are no screw-holes for 2.5" drive in 3.5" caddies.
I make this one to be compatible with any caddy (2.5" compatible or not) for any computer (tower, server, ramdom PC, ..).