Just what I needed for my Octatrack - got the rack ears made by Elektron via Thomann too and everything slotted together perfectly in a few minutes.
It's not clear on the description but this item does come with the screws you need.
Solidly built and just the right size with enough space underneath the unit to store the PSU, Cables, Headphones etc...
The ergonomics are vastly improved by the tilted rails, so much better than working with the Octatrack flat on the table.
I like that it has lock holes on the clasps at the side too. Nothing that's going to stop a determined event, but with a cable lock this will stop the opportunist running off with it.
Quite heavy, but that's the trade off for good protection I guess.
If you're gigging with your Elektron gear, this box is an ideal solution!
Highly recommended!