Green lines make Zometool more versatile and complex. But because of their design (double kinked) each strut can go into a hole in one of five different ways adding 30 new directions from each ball!. And there is much more:

Green lengths are in the Golden Proportion: if a Blue Line has length 1, then a Green Line has a length of √2 (or √2/2: Half Greens). Like other lines in the Zometool, relative lengths of the Green Lines are in the Golden Proportion (i.e., a short Green plus a medium Green are the same length as a long Green, and the ratio of short to medium is the same as medium to long). You can make a Golden Rectangle with Green Lines (just like Blues, only √2 bigger!) Conway's Cosmogram (=Kepler's Kosmos) features an octahedron with its edges intersected in the Golden Proportion by an icosahedron.

Green Lines with 222 parts and coloured description.