[gldnbrwncouches]

I've recently been getting books I purchase delivered through a service called Bookfunnel. They offer downloading a book in multiple formats if available for that book. Among the standard formats (epub, mobi, kepub, pdf, etc) there's also an option to download a "Kindle Epub file".

The kepub file downloads as "<bookname>.kepub.epub". In my experience, leaving it in this dual-extension style filename format will only show up as an "epub" in Calibre and it only stores one of each format per book. So I remove the ".epub" at the end and import it into Calibre as a ".kepub" file for the book, which allows for storing both the kepub and epub files and it works as expected when transferring it to my Kobo devices.

Similarly, the "Kindle Epub file" looks like "<bookname>.kindle.epub". I've been doing the same thing as the kepub so it ends up getting stored as a ".kindle" extension file for the book in Calibre. However, this means there's no real way for Calibre to interpret using it since ".kindle" isn't a real ebook format, but I keep it just in case it actually has better formatting structure for Kindle readers. Ideally, if it is actually better than the regular epub for kindle readers, this is the file I'd want to use for syncing over usb or sending to kindle via email, now that epub is actually supported there.

Two questions about this:

1. Is there a better way to import or store these so that I could more easily use them with Calibre and a Kindle device?

2. Does anyone whose seen these ".kindle.epub" files know if they carry any meaningful difference in formatting or structure than the regular epub files?