Left/Right indicator shoelace beads - Learning assistance

According to Leiden University in the Netherlands, 15% of the global population is struggling to distinguish left and right. Personally, I don't know any person who is having that issue, though I think my little project could help someone :D

I created two little beads in 3 versions:
- Normal - which is self-explanatory,
- Abstract - indicates sides without it being obvious,
- Abstract+ - More abstracted variation for people who don't want to expose themselves with having this disorder.

I recommend printing with PETG due to its strength and flexibility. TPU should be even better.

I also included STEP file with a blank piece for easier modification.