The great thing about (at least Prusa) filament boxes is that they have labels on the side and you can see what's inside. But when you take the filalement out, you can only really see it's colour. So I needed labels to make my shelving work properly for me.
These clips fit over a spindle of 23.6mm in diameter snugly.
The clips themselves are generic, and the printed labels slide and friction fit in place. You can remove the label and fit another if you like.
Print out a lot of labels so you can switch out as needed. They can be stored in the storage boxes in the RAW STL files.
I made a lot more labels, so if you need something specific, I can probably create it if I don't have it.
And yes, I can store PETG in the open in my house for quite a while :)