Phaetus CoCoon Filament Dryer Box

The Phaetus CoCoon is a sealed dry box for a standard 1 kg spool (up to about 204 mm across and 70 mm wide). It uses desiccant rather than heat, with room for up to 400 g, and the display shows humidity, temperature, and remaining filament weight. Phaetus says it can hold humidity below 10% RH for two weeks, and it alerts you when the desiccant needs replacing. Opened on camera for a live stream and a YouTube video, never used.

Feed filament out to the printer while the spool stays in the box. It runs on three AAA batteries or USB-C. Use it to keep already-dry filament dry. If a spool is already wet, dry it in a heated dryer first.