From:
http://www.warboats.org/mk3.htmBuilders: Marinette Marine, Wisc. and Peterson Builders, Sturgeon Bay, Wisc.
The PB Mk III was developed as a multi-mission inshore warfare craft for U.S. and foreign naval service. The U.S. craft are operated by the active SBUs.
Design: The Mk III is a modified commercial craft used to support offshore drilling platforms in the Gulf of Mexico. These craft are of all-aluminum construction with their pilot house offset to starboard to provide maximum deck space for weapons and equipment. The craft has low radar cross-section and quiet engines for clandestine operations. Mission duration is up to five days.
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Screen capture from PN video
