This a specimen for tensile testing in accordance with ASTM D638 "Standard Test Method for Tensile Properties of Plastics". It is a Type 1 specimen to be made from rigid plastic.

Tensile testing of RepRap printed specimens is being performed at the Michigan Tech Open Sustainability Technology Research Group mse.mtu.edu/~pearce/Index.html. Specific information about the testing can be found here appropedia.org/Mechanical_testing_of_polymer_components_made_with_the_RepRap_3-D_printer.