This is a replacement for the SD Card slot... dummy?... blank?... filler? I don't know - the little plastic thing that plugs into the SD card slot in your laptop that keeps dust out or whatever. This is modeled after the blank that came with my Latitude e7270, but will probably fit others. I really like the red, since it makes it easier to find when I take it out. Because of the fine detail, you should print with a fairly small layer height. I used 0.12 and it worked out great. 100% infill is also probably a good idea. There are two versions: One that says "TOP" on the, you know, top, and one that is blank.