Navy Shellback Court Of Neptune Rex Coffee Mug Printed In America! The United States Navy has celebrated the crossing of the equatorial line with a ceremony called the Shellback ceremony. You will stand before the Court of Neptune Rex when this happens and what happens next will change your life as a US Navy sailor. In the U.S. Navy, when a ship crosses the equator a time-honored ceremony takes place. This is a long standing Navy tradition and an event no sailor ever forgets. With few exceptions, those who have been inducted into the "mysteries of the deep" by Neptunus Rex and his Royal court, count the experience as a highlight of their naval career. This Navy Shellback Court of Neptune Rex Navy design is created for all US Navy sailors that have been to court.