I was looking for a desiccant holder that would go with the spools while it was in the vacuum bags but couldn't find one I liked.

Holders that go inside the center/hub of the spool are sealed off from the filament once the bags are vacuumed, so I wanted one that went outside. It needed to allow visual confirmation of the color indication of the desiccant while on the spool, it needed to fit multiple size spools, and it needed to be robust and quick to print.

Four Sizes to choose from 45mm, 50mm, 55mm, and 60mm. 

I opened up tinkercad and here is what I came up with: three models; 45mm, 50mm, and 60mm tall canisters. The 60mm fits perfectly inside the Bambu spools. The 50mm fits many of the other 1kg spools. the 45mm fits the colorFab 750g spools. A 55mm was requested by @wkearney99, and was uploaded on 24/11/23. If there are any other specific requests, I will do what I can to oblige.

The snap on lid is interchangeable between all four sizes. 

The containers are only perforated on the spool side, and when printed in transparent PLA or PETG, you should be able to see the color indicating desiccant. I designed them as spiraling vase mode prints with 1mm walls, so they are pretty strong and fairly quick to print.

Each size is set up on separate plates, and each plate is set up to print all four parts as objects so each part can be printed in vase mode.

Update 24/12/2: As a request from @Val3D,  I created and added desiccant boxes with perforations on front and back.