Three Chilean Navy Type 23 frigates will be upgraded with the MK 41 Vertical Launching Systems (VLS) and they will be armed with the Evolved Seasparrow Missiles (ESSMs).
By U.S. Navy photo by Mass Communication Specialist Seaman Matthew J. Haran [Public domain], via Wikimedia Commons
Raytheon, BAE Systems and Lockheed Martin are the contractors implementing the upgrade.