Gridfinity 1x1 Bin to store small size discs (23mm diameter) compatible with the discbound planner system (Arc, Happy Planner, etc.) Holds 7 discs, the number needed for a junior size planner (that's what I use).

The discs fit nice and snug, so they don't fall if the bin isn't full, and you can take them with ease.

I've printed these with PLA 0.6 nozzle 0.48 height, but also the most common setup of 0.4 nozzle at 0.2 height with great results. Both with 10 to 15% infill.