This is a hybrid between 2 prints I had found on Thingiverse that had ups and downs. The first one fit perfectly, but the front looked horrendous. The second didn't fit well, but looked great. I mixed them and used that to make a cleaner mesh model that was hence much easier to print reliably.
The drives are for small form factor (SFF) DL380p/DL360p Gen8 HP Enterprise servers. The caddies should fit anything that also takes the Gen8 caddies, which includes at least Gen9 as far as I know.
Assembly doesn't require any hardware, just flex the branches of the caddy enough to put the nubs inside the 2.5" drive's side mount holes and it'll be secure. When connected, the SAS/SATA connection to the drive will hold the whole thing in place, but will still be easy to remove intentionally.
The objectives I had when making this model were:
To do this, I used blender since it can easily work with STL files and doesn't really care about bad meshes. I stitched the original models together and used the result as a 1:1 copy of the mesh I then had to create. 30 minutes later, I had something with roughly the exact same dimensions down to the smallest coordinate units Blender could do. A few slices and inspections later, I adjusted the model to ensure it would always print correctly and without being prone to print failures (which are common with bad meshes).
The author hasn't provided the model origin yet.