The CoreBox Pro motherboard with two SATA terminals is useless unless you add it.
I attach a SATA cable from the used CoreBox to the CoreBox Pro and operate it with 3 drives.
I also removed the m.2 SSD that came with the CoreBox and used it for other purposes.
The CoreBox Pro’s m.2 specification is NVMe, but it also supports m.2 SATA SSDs.
CHUWI may sell or provide this SATA cable free of charge to help expand CoreBox Pro.
The 2.5inc drive mounter should also be changed to one that can mount two. It is preferable that this part is also sold or provided free of charge.
Still, my environment is half-baked, and when it’s in place, I have a lot to try. Also.
In CoreBoxX, the terminals attached to this CoreBox do not fit. You can’t use it unless you make it yourself.
In the future, I would like to make this CoreBox X cable by myself 
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