Kodachrome 40 Super 8 Film 4-Pack

This is a set of Kodak Kodachrome 40 Super 8 film.

I found these while clearing out unwanted items at my parents' house, and I'm listing them because I don't need them.
Three out of the four are unopened, but the boxes are dirty as they were stored in a warehouse.

I believe these are for video cameras (?), but I don't know much about them, so please refer to the photos for everything.
I hope to sell them to someone who understands their value.

Please only purchase if you understand that these are used items stored in a private home in their current condition, and that all sales are final (no claims, no returns).

Thank you for looking.