Unsinkability
Today, this "unsinkable" attribute is not exclusive to Boston Whalers. All motorboats (and certain other boat types) under twenty (20) feet, manufactured for sale in the United States are required by law to have positive flotation, such that a completely swamped boat will still float. This is accomplished through the use of closed cell foam, or other non-permeable material. Boston Whaler,however, does claim to exceed the Coast Guard requirements.
Further demonstrations have been done to prove how "unsinkable" the boats are. In March 2007, a 19' Guardian was shot with 7.62mm rounds from an M60 machine gun. The boat did not sink, although it was full of holes. The engine was unable to start because of its having been destroyed during the test.
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