Why is there a watermark on the mockup preview?

Like the other tools, free mockups come with a light preview watermark so you can generate and inspect the whole pack before paying. Once you unlock the book, the same mockups export without the watermark. See Why is my export watermarked?

The Mockup Pack covers the Social Pack too — the same unlock that clears the watermark on your 3D shots clears it on the videos and social stills. See Can I make a video of my book?