Blue Angels Avionics Once a Blue Angel USN USMC Challenge Coin. Coin is approximately 3 inches wide by 1.5 inches high. I sell high quality, desirable, collectible challenge coins. If you are looking for a specific coin for your collection, as a “memento” from a previous unit, to replace a coin that was lost, or for a gift, there is a good chance I may have it so please check my other listings! Frequently Asked Questions – Please read before you message me. If you are purchasing multiple coins please let me know prior to paying and I will send a combined invoice. Small or Medium Flat Rate Box. For any questions not covered above.