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I've heard of SATA, but "LFF SATA" as listed on HP's specs page (archive) is a new one for me.
What does the "LFF" bit mean?
LFF == Large Form Factor == 3.5" hard drive
SFF == Small Form Factor == 2.5" hard drive
They had to start designating it since many servers and even desktops now are shipping with SFF drives to save physical space and/or cram more drives in.
To complement Peelman's answer, here is HP's official documentation on the topic of all the other disk vocabulary that goes with LFF and SFF:
HPE Hard Disk Drives - a00001287enw - 15825 - Worldwide - V10 - 13-August-2018