I've printed a bunch of those great KYZ FF2 High Airflow Spool Desiccant Holders by KYZ Design, I've been using them for about a year. I made a remix of the cap for the desiccant holder to be printed in transparent PETG, with settings optimized to make the cap see-through. So you can just hold it up to a light and tell if your colour changing desiccant needs to be dried. Enjoy!