SAN DIEGO (March 15, 2021) Lt. Xavier Pierce from Reaford, N.C., puts on a health-monitoring ring a part of the Crew Readiness, Endurance, and Watch Standing (CREW) study aboard the Wasp-class amphibious assault ship USS Essex (LHD 2). Essex is homeported in San Diego. (U.S. Navy photo by Mass Communication Specialist 3rd Class Isaak Martinez)