I spent an exhausting search for Primaloft pillows to replace the ones I had enjoyed for years. These from O.co are indeed, Primaloft. The only reason I gave them four stars is that we have no option to choose between firmness levels. I ordered two in Standard size and two in the King size. Even though the tag on each size states, "Primaloft-Support" the pillows are vastly different. The Standard sizes are very soft and comfortable, but not so soft that they feel flat. The King size are very firm - too firm to be comfortable. They don't seem to flatten at all when you lay on them so you're kind of propped up. They're great for leaning back on and reading in bed, but way to ofirm to sleep on. I kept all these pillows because the price was right. If the King size had been the firmness of the Standard I would have given them five stars.