The other day I reinstalled windows after deciding to remove linux from my computer completely. I have windows 10 on my SSD and a secondary hard disk for extra stuff. I thought I removed all the linux data from the hard drive, which is my guess as to what this is. I unplugged the HDD when I installed windows 10, so I don't think it can be a boot partition, unless Windows created one on it somehow. I just want to make sure it is safe to delete this partition before I do. Here is a screenshot https://drive.google.com/open?id=1JLdV4xmmLyfsZAfoIHUjecERiQciIFFr