Airman 1st Class Michael Balbaugh demonstrates how to check the seal of the M-50 Joint Service General Purpose Mask Nov. 5, 2009, at Ramstein Air Base, Germany. The mask has two filters as opposed to the one canister filter on the MCU-2 mask. Airman Balbaugh is from the 886th Civil Engineer Squadron as a readiness and emergency management apprentice. (U.S. Air Force photo/Senior Airman Amanda Dick)