Lifestyles SKYN condoms are one of only a handful of available brands of non-latex condoms. These polyisoprene condoms were FDA approved in November 2008 for the prevention of pregnancy as well as for sexually transmitted diseases.
In the US, the Marines are part of the Navy. The Navy is the seagoing part of the US military. They man the ships, and submarines, and fly the jets from aircraft carriers. The marines were originally soldiers specially trained for ship to ship combat back in the days of sailing ships.
1 The Army is much larger than the Marine Corps.  The Marine Corps is an amphibious, integrated force under the Department of the Navy and relies on Navy support technical and medical support, whereas the Army is a land force which trains its own medical, dental, and religious personnel.