Air Force Tech. Sgt. Corey Briggs, right, and Staff Sgt. Nathan Knight handle a sample of liquid oxygen at Bagram Airfield, Afghanistan, Sept. 14, 2016. Briggs, a cryogenics technician, and Knight, a cryogenics supervisor, are assigned to the 455th Expeditionary Logistics Readiness Squadron. Air Force photo by Senior Airman Justyn M. Freeman