I use this shelf for a Focusrite Clarett 4Pre, which fits in it perfectly.
The shelf is well made and provides several useful holes for attaching devices and/or enabling air circulation (good for devices which heat up).
The only minor negative is that there is a gap between the rack ears and the front of the shelf. If would have preferred it if the shelf came all the way to the rack ears.
Overall, it is a good shelf for an uncommon format. I hope Flyht Pro and other manufacturers will continue to expand their half-rack range.