What do the symbols mean in the 7zip Open Archive context menu?

I have a 7zip file that I could not open. When I right clicked on it, I saw an open archive submenu. When I clicked on the ‘#’ option, I was able to open the archive. I can’t seem to find any documentation on what this ‘#’ means in this context. Could someone explain what the *, #, and #:e mean in the Open archive context menu?

Photo of 7zip Open Archive submenu