SAN DIEGO (Dec. 7, 2020) Marines with Co. K, 3rd Battalion, 5th Marine Regiment, 1st Marine Division, sit in a CH-53 Sea Stallion during an air assault as part of Steel Knight/Dawn Blitz (SK/DB) 21 at Naval Air Facility El Centro, Calif., Dec. 7, 2020. Strong, mutually supporting relationships between 1st Marine Division, I Marine Expeditionary Force units, and naval units are enhanced by large combined-arms exercises like SK/DB 21. (U.S. Marine Corps photo by Sgt. Miguel A. Rosales)