I wanted to find a quicker way to print an in-spool desiccant basket and stumbled across these tea strainers (type 3). They're 5.8cm OD / 4.8cm ID x 4.4cm, which fits nicely inside my filament spools. For spools with a larger diameter, you can print a washer to keep it from sliding through.
This is a useful model for those using the A1, or anyone who doesn't want or can't have an in-spool desiccant container during printing.