That is a zip file? Some file managers open that and don't extract except to access the file you want and then it's temporary as well.
I'm looking for an OSX app that can give me an encrypted volume or folder, for which I must manually enter the password when I want to open it. I would like backup services to see it as a single opaque file when it's not open, because I don't want the contents to be backed up in the clear.
When I used to use Windows I had a tool called Kryptel, but I haven't yet found anything similar for Mac.
Free is best, but I'm willing to pay a little money for something worthwhile. Any ideas?

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