Spool containers - silica gel with hygrometer

A silica gel container that is placed in the center of the spool for long-term storage of filaments susceptible to humidity. For completeness, I'm also including a cap from https://www.printables.com/model/558743-prusament-spool-silicadessiccant-cap-without-hygro if you don't want to place a hydrometer. If anyone needs other dimensions of the part - I can add...