A member of Sea-Air-Land (SEAL) Team Three emerges from the water after crossing a river during a field training exercise.  The end of his M16A1 rifle is taped over to prevent mud from entering the barrel.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/127906254@N06">National Museum of the U.S. Navy</a>
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/127906254@N06/19075614198/">DN-ST-88-00543</a>