What does DAP mean in disk model ST3300655FC-DAP?

Question

Hard disks

From Asian "friends" came a postal item with hard drives for a disk shelf.
The hard drives turned out to be some kind of ST3300655FC-DAP instead of simple ST3300655FC and did not fit.
Shelf said incompatible. Although the disks themselves have ENGENIO PART NUMBER 22145-04
What does this postscript mean?

Answer 1

I'm not sure, but it looks like some sort of vendor-lock modification. Possibly the firmware is modified.