I holds my 1U and 2U units, so it does what it's meant to do, but I needed to put some sticking felt underneath on of the 4 rubber cilinders that touch the desk, to make it sturdy. Also: the metal (or whatever it is) damages quite easily: it already looks worn after fixing my 2 modules.
I've removed the top bar so that it fits my 2 units better, with more space underneath for cables et cetera.
The other thing I don't like is that the foot base sticks out a lot, in front. Unnecessary, because the centre of weight is nót on the front side. But I'm keeping it, it's cheap and I'm Dutch after all :-)
Oh, don't forget to order the Adam Hall 5621 Plain Nylon rings as well!