This is an Adjustable Spool Holder for Silica Gel (Desiccant) / Spool Weight developed specifically for the Hydra AMS and Bambu Lab AMS but it should be useful for regular dry boxes as well where the spool is on top of rollers / roller bearings.

The internal compartment can be filled with silica gel to keep the filament dry or you can fill it with something else to add some weight if you prefer.

It rooms around 40 g of silica gel. Make sure you fully pack it with silica gel beads. If it's not fully packed it can deform the beads when rotating. You could also use bags of silica.

It fits most spools with a width between 40 and 80 mm. Keep in mind, for the Bambu Lab AMS the max spool width is 68 mm and for Hydra AMS it is 75 mm.

It prints in three parts completely without supports.