KitGuru reviewed the QNAP TS-431XeU-8G 4-bay Rackmount NAS
A quote from the article:
QNAP’s TS-431XeU 1U rackmount NAS sits in the companies SMB product line and has been designed with smaller racks in mind as it has a much shorter depth than standard. It comes with four drive bays, quad-core CPU power and an integrated 10GbE SFP+ port.QNAP TS-431XeU-8G 4-bay Rackmount NAS Review
With its 291mm depth, QNAP has designed the 4-bay TS-431XeU with the smaller or space constrained office in mind, where a full size rack isn’t an option but a smaller unit can be accommodated. Apart from its shallower than standard depth, the other major feature of the NAS is the integrated 10GbE port, but this isn’t a standard RJ45 10GbE port but rather a SFP+ one.