Double boiler insert. I’ve only seen 2 ever. This one fits this 3 qt stock pot, the 2 and 4 qt stock pots, and the 3 qt sauce pan. There is also a ceramic one that is technically a Bain Marie, and it fits the 2 qt sauce pan. See the post here that I’ve written that contains the set and you can see what it looks like.
Fondue pot. This is the same size pan as the smallest (2 qt) stock pot, but with a single handle. I don’t believe they made them very long, because I’ve not seen one with a signature, but there may be one out there. This is a limited edition.