The scroll case may find use whenever one needs to transport a short missive in a dignified, weather-resistant case.
Use a medium length of sturdy ribbon to fasten it snugly between a raven’s wings, with an X-harness across the bird’s keel.
Can also hold a small amount of iocaine powder.
The cap and tube should fit together snugly, but if you would like the cap to be silently removable I suggest wiping the interior plug with a little acetone. This will smooth out the ridges left by the printing process and reduce friction when inserting into the tube.
A 55mmx140mm sheet of paper will roll nicely and fit into the tube. A template .svg is included for your convenience. Ciphering and encryption of messages is left as an exercise for the reader.