I could not get the original K2 Clip to print well and did not feel like I needed the additional slots of different sizes. I designed my clip without the unnecessary openings and additional slots. I also adjusted the slots to work better with my filament. Mine also has the locking center and seems to work well so far. I have included the parametric FreeCad file if adjustments are necessary. In the picture of the clip in use, it is the red one. The green ones are the K2 Clip.
02/10/202 - per request from a commenter, I have added STL files of versions with labels for PLA, PET, and ASA.
The author remixed this model.
I have added STL files of versions with labels for PLA, PET, and ASA.