Two different dividers for the small drawers of this STANLEY organzier: https://www.stanleyworks.de/produkt/1-93-980/kleinteilemagazin-mit-30-schubladen (model 1-93-980), also sometimes branded as CRAFTSMAN .
These lock in place (you can pick up the drawer by the dividers!) by having tiny nubs at the bottom that slot below the tabs on the rails, plus thickened sides that add friction inside the rails.
I printed them with a 0.4 mm nozzle and 0.2 mm layer height in PETG, standing upright with a brim.
The author marked this model as their own original creation.