I made this because I needed a neat place to store my tips, so I figured I'd put them in my heat set insert bin so they're always ready to use!
The tips I use are these: https://a.co/d/ckWd5pk
They should fit any soldering tip that has an outer diameter of 6.5MM at most, and each hole is labeled with what metric size of insert they are used for.
The author remixed this model.