Sata Data Cable, Radio Shack What Is A '7D SATA Data Cable'?

What is a '7D SATA data cable'? - sata data cable, radio shack

It differs from a normal SATA cable? Is it to show the quality of the cable (eg CAT5 CAT6 cable, Ethernet)?

I'll buy a round RAID and a SATA cable connector is 7D. This is the tower

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