External drives usable in NAS?

I’ve got 6 HD’s 5 of them are WD. But they are external.
Now I want to buy A Nas. Can i Use the external disks or 4 of them in this NAS ?

It depends. You’ll have to cut them out of their enclosures, and then if they happen to be SATA drives with standard connectors, and they’re not Black Listed WD drives, then yeah, they’d possibly work.

Well they seem to be all SATA.