I designed this one because my brother was asking for some pot for carrying some cigarettes that prevents smell going out.
Model is scaled so it can be printed as is and cap will fit perfectly.
I made two different sizes and used some o-rings to prevent smell and tobacco going out.
For the little model I'm using 9.5x12.7mm o-ring.
For the big model I'm using 19.1x23.8mm o-ring.
I'm sure other o-ring can be used, print it and visit your local store to see what they have.
I would like to thank you to Dan Kirshner for sharing his thread library that produces standardized ISO threads. You can find it here http://dkprojects.net/openscad-threads/
It can be used for many other things more.
Use, share and enjoy the design!