U.S. Air Force Senior Airman Steven C. Rehana, 380th Expeditionary Logistics Readiness Squadron cryogenics technician, opens a valve to release liquid oxygen at Al Dhafra Air Base, United Arab Emirates, April 15, 2021. Airmen with the cryogenics shop provide sustainable air for aircrew members to breathe at high altitudes. (U.S. Air Force photo by Staff Sgt. Miranda A. Loera)