Senior Airman Timothy Milders and Airman Calvin Daniels, 28th Maintenance Squadron aircrew egress system technicians, install safety pins and arm straps onto an Advance Concept Ejection Seat II during training at Ellsworth Air Force Base, S.D., Jan. 23, 2012.There are four ACES II installed in every B-1B. (U.S. Air Force photo by Airman 1st Class Zachary Hada/Released)