I designed this because I couldn't found any low-profile keycaps that would fit my Keychron K3.
Print on a resin printer to get the best quality.
I also added a version for filament printers with higher tolerances so it fits. I sliced it in a funny way so the curvature on the top of the key prints fine and no supports are required for the middle part:
The author hasn't provided the model origin yet.