Four Dutch navy Walrus class submarines are receiving Passive Sonar Processing Systems from Kongsberg of Norway. The PSPS are as part of the Dutch navy\'s Sonar Suite Modification Project. The Passive Sonar Processing System integrates hydrophone data from all passive sonars aboard a submarine into one processing system, producing more accurate target solutions in shorter time and giving sonar operators flexibility to use passive sonar data from any combination of sonars to solve their tasks. The PSPS to be delivered will take full advantage of the Sonar System Upgrade solutions that have been developed and are in production for the Norwegian Ula class submarines. \"There exists in the world market a large number of submarines in need of a mid-life, or life extension, update,\" said Kongsberg Defense Systems Executive Vice President Nils-Oddvar Hagen. \"In this context, this is yet another important reference contract for Kongsberg that will further strengthen our position as supplier of integrated submarine systems.\"