Check the listing for details. * US Navy Challenge Coin, Certified Shellback Navigated The Globe Crossing Line. Condition: New, Made in United States. Listed at 7.95 USD. The US Navy Challenge Coin is an original collectible item featuring a shellback navigated the globe crossing the equator line design. This challenge coin is a certified piece that showcases the theme of militaria and is a unique representation of the United States Navy. It is a prized possession for collectors and enthusiasts of military memorabilia, making it a valuable addition to any collection. Size is 40mm or 1.5 inches in diameter and comes in a clear plastic capsule to protect it.