The phantom is homogeneous and elliptical in shape. It properly represents human anatomy in size and proportion. It measures 30 cm long x 30 cm wide x 20 cm thick (PA). The phantom is constructed of proprietary tissue equivalent epoxy materials. Linear attenuations of the simulated tissues are within 1% of actual attenuation for bone and water from 50 keV to 15 MeV. Numerous options are available.