I think these are polycarbonate made on Stratasys machines. It's really a replacement for the slightly more labor-intensive methods of making stuff out of balsa

I think these are polycarbonate made on Stratasys machines. It's really a replacement for the slightly more labor-intensive methods of making stuff out of balsa and styrofoam, sanding and painting, fiberglassing, etc. You still need to sand and paint, to be sure, but... fairly precise shapes can be made directly without needing forms and guides, etc, so that saves on labor. Polycarbonate has a higher heat deflection temperature than the typical epoxies one might use in this sort of application. Stiffness is a little lower than epoxy, but not by much.