I have these for my 10TB HGST drives that I have that are 4KN drives. They worked PERFECTLY on these drives. I know that if the drives wouldn't spin up I would have to cut the ORANGE wire and that would fix it for this drive. but I had none of these problems. One of my cables, I ordered two, broke, so I took a star off, otherwise it would have been 5 stars. I get full speeds like I should and it didn't break the bank.