USHUS is an integrated sonar system[1] developed by the Naval Physical and Oceanographic Laboratory (NPOL) of the Defence Research and Development Organisation (DRDO), India, for use in submarines of the Indian Navy.[2][3] It is primarily designed to be used in Sindhughosh class submarines,[4][5] though it is reported to be fitted in the Arihant-class nuclear-powered ballistic missile submarines as well.[6][7][8] USHUS is reported to be superior to its Russian equivalents.[9]