***ONLY SEAPORT-NxG MAC HOLDERS SHOULD RESPOND TO THIS SOURCES SOUGHT NOTICE*** Sources Sought Announcement for a services procurement supporting the Integrated Undersea Surveillance System (IUSS) Product Support Facility (PSF). The Government anticipates this effort to be a Cost-Plus-Fixed-Fee (CPFF) type SeaPort Next Generation (SeaPort-NxG) Task Order with a one-year base period, four one-year option periods and a six-month option to extend in accordance with FAR 52.217-8. Please see attachments to this post for more information. Submissions from non-SeaPort-NxG MAC holders will not be considered.