What Proto Labs calls its “Protogami” consists of six tetrahedra, each of which holds four flat black triangles made from a particular resin. In turn, each side of a tetrahedron features a particular resin with a certain finish. For example, the tetrahedron that holds thermoplastic elastomer (TPE) chips shows examples of TPE with a C1 finish (600 grit stone, 10 to 12 Ra); an A2 finish (grade #2 diamond buff, 1 to 2 Ra); an F0 finish (noncosmetic); and a T2 finish (C1 followed by a medium-bead blast). The other chips are made of high-density polyethylene (HDPE), polycarbonate (PC), glass-filled nylon (PA-GF), acrylonitrite butadiene styrene (ABS), and acetal. Each resin sample features the same four finishes. The Protomold Protogami is now in production, and kits are available at no charge here.