The CIRS Model 801-P phantom is our most realistic, tissue equivalent phantom available. The phantom was designed for use in diagnostic radiology and radiation therapy for imaging dosimetry teaching and demonstration applications. All anatomical dimensions of the phantom are based on The Visible Human Project (VHP) data sets that serve as a reference for the study of human anatomy and are available through the National Library of Medicine. CIRS has combined this anatomical detail with our advanced tissue mimicking technology. The phantom is made from proprietary epoxy materials that mimic the density and radiation attenuation properties of human tissue within 1% from 50 keV to 25 MeV. It contains anatomically precise bone, cartilage, spinal cord, vertebral disks, muscle, intestines, bladder, prostate, rectum and interstitial fat.