I got this stick as an upgrade several years ago when I bought my Powerbook G4. It didn't run well in it, but I held on to it anyway. It later ran in a Intel MacBook without problems. The RAM is apparently from Lifetime Memory Products so you can't RMA it directly as a consumer. All I can tell you is this caused my Powerbook G4 to randomly lock up, but it worked without causing any issues in an Intel Macbook. My guess is that the boards in the Powerbooks were just really picky on what RAM you used (and I was running it with a different brand 512 stick). So I'm asking $5 plus shipping. I'm only going to ship to the US just to keep shipping costs down.