WD40EFRX WD RED Plus in external USB Base shows 1.6TB

As title indicates a new WD RED Plus 4TB (WD40EFRX) dropped into an external USB NextStar base shows up as 1678.02 GB Unallocated. Windows 10 Disk Management tool.
Ideas as to get the full capacity out of the drive in this setup?
Thanks in advance for any insight, or obvious stupid blunders on my part!