Thank you! I have a Keystone box, but it does not have the picture like yours. Now I won't have to do the research on that one. These will go with my Singer 12, along with a few other very old attachments.
I'm trying to talk myself into only having really old Singers - and attachments for them, and letting the rest of my old attachments find homes with machines they go with. I think one of the hardest to part with is going to be the White set - the ones with the box that says "White is King" on it. But I know I don't want to add a boat shuttle White to the collection.
Though I don't have to decide anything until I get moved into my new building - and then see what I've got room for.