Zometool originally produced these “GB1” struts, having the length of B1 struts but in the green direction, for the purpose of building certain Archimedean solids exactly. A few years ago, I wrote an essay about these struts that tells the whole story. In that essay, I offered to model these struts in case anyone wanted to 3D-print them, and now someone has accepted my offer… so here they are, as a vZome design and a downloadable STL file.
This design tries to exactly copy the green strut design from Zometool. Even so, they may not exactly reproduce the tight fit when constructing the compound of five tetrahedra, as mentioned in my essay.
The struts are connected in a group of six due to the pricing model from the original Shapeways, on the assumption that the revived Shapeways will use a similar model. You are, of course, free to use any SLS printing service you like; there are many options now.
This design is not really designed for printing on a typical home FDM printer. If you are interested in a better design for that, contact me through the vZome Discord server.