IS (IS〈インフィニット・ストラトス〉, IS ) is a Japanese light novel series by Izuru Yumizuru with illustrations provided by Okiura. As of April 2011, 7 volumes have been published by Media Factory under their MF Bunko J label. A manga adaptation by Kenji Akahoshi started serialization in the seinen manga magazine Monthly Comic Alive on May 27, 2010. An anime adaptation aired in Japan from January 6 to March 31, 2011.