Iridium Communications Inc. provides satellite voice and data communications services to businesses, the U.S. and foreign governments, non-governmental organizations, and consumers worldwide. It offers post-paid mobile voice and data satellite communications services; prepaid mobile voice satellite communications services; high-speed data services; machine-to-machine services for sending and receiving data from one location to other, such as from fixed and mobile assets in remote locations to a central monitoring station; and ancillary services, including inbound connections from the public switched telephone networks, SMS, SIM activation and reactivation, and other peripheral services. The company also provides research and development services that assist customers in developing new technologies compatible with its systems. In addition, it offers voice and data equipment, including satellite handsets, voice and data modems, high-speed data devices, and machine-to-machine data devices. Further, the company supplies accessories that include holsters, ear buds, portable auxiliary antennas, antenna adaptors, and USB data cables and charging units. It serves various markets, including emergency services, maritime, government, utilities, oil and gas, mining, leisure, forestry, and construction and transportation. The company sells its products and services to commercial end-users through a wholesale distribution network of service providers, value added resellers, and value-added manufacturers. As of December 31, 2009, it had approximately 369,000 subscribers. The company is headquartered in Bethesda, Maryland.