Japan's Oki Electric Industry (OKI) has signed a supply contract with Mitsubishi Heavy Industries (MHI) for towed passive sonar and related equipment to be installed on Australia's new general-purpose frigates. The company has designed and manufactured underwater acoustic sensors and related equipment, primarily for defense applications. For sonar systems used by the Japan Maritime Self-Defense Force, OKI provides comprehensive support throughout the product lifecycle, from design to maintenance. In August 2025, the Australian government selected Japan's improved Mogami-class frigate, known as the "06FFM," an upgraded version of the Mogami-class frigate, for its new General Purpose Frigate program. The upgraded Mogami-class frigate will have a range of up to 10,000 nautical miles and a 32-cell vertical launch system (VLS).