Contract Amendment for GÜR-Class Submarine Mid-Life Upgrade (MLU) project was signed between the STM-Aselsan-ASFAT-Havelsan Joint Venture (JV), and the Secretariat for Defence Industries (SSB) on January 17, 2024. With the Contract Amendment, the GÜR-Class Submarine Mid-Life Upgrade activities will be carried out as part of the PREVEZE-Class Submarine Mid-Life Upgrade Project.

The contract aims to modernize certain critical navigation, engine, and communication systems of the GÜR-Class Submarines in the first phase. The Joint Venture is responsible for system procurement and platform integration, and the project is planned to be completed within 6 years under STM's leadership.