International Isotopes Inc. manufactures and sells nuclear medicine calibration and reference standards, cobalt-60 products, and radiopharmaceutical and radiochemical contract manufacturing services in the United States and internationally. It operates through five segments: Nuclear Medicine Standards, Cobalt Products, Radiochemical Products, Radiological Services, and Fluorine Products. The Nuclear Medicine Standards segment manufactures sources and standards associated with single photon emission computed and positron emission tomography imaging, patient positioning, and calibration or operational testing of dose measuring equipment for the nuclear pharmacy industry. It offers flood sources, dose calibrators, rod sources, flexible and rigid rulers, spot and pen point markers, and various specialty design items. The Cobalt Products segment produces bulk cobalt; fabricates cobalt capsules for radiation therapy and various industrial applications; and recycles expended cobalt sources. The Radiochemical Products segment produces and distributes various isotopically pure radiochemicals and sodium iodide I-131 generic drug product for medical, industrial, and research applications. The Radiological Services segment provides flood source disposal and gemstones processing services. The Fluorine Products segment is involved in the production of small-scale qualification samples of high purity fluoride gas for various industrial applications, as well as development of laboratory and analytical processes required to support the planned uranium de-conversion and fluorine extraction facility. It sells its products directly to end users and distributors. International Isotopes Inc. was incorporated in 1995 and is headquartered in Idaho Falls, Idaho.