I have fond memories of playing with connectable shapes that looked similar to these as a child, and so I decided to try to make a version that could be 3D printed.  My goal was to create something that was easy to attach and pull apart in a bunch of different ways, so that they are fun to interact with.  And I also wanted them to hold together well - allowing for structures that can stretch out in interesting directions without falling apart.  After several iterations, I came up with this version that my family really likes, and I hope you can enjoy as well.

This is an easy print that requires no supports or special settings, and can be uniformly scaled if you'd like a different size (the original has an outer diameter of 7 cm).  I wanted to print a bunch of them, so I'm also attaching the 3MF file that shows the settings I used in the PrusaSlicer to try and get a fast print that was still plenty strong.  

The chamfered  design also allows for interesting options using a color change at different layer heights as well.  Have fun with your color choices!