Hi, I moved your thread to Rapid Threads since your technical issue seems to be solved.
When someone sells a head, they'll show a watermarked "flat" (or image of the texture).
Here's an example of a watermarked head, you can see the stripes:
Heads are watermarked so people can't steal them. Once the head is sold, they'll send them the full texture without the watermark so that the new owner can use it.