U.S. Marines with Engineer Company, Combat Logistics Battalion 1, and Marine Wing Support Squadron 372, currently deployed in support of Special Purpose Marine Air Ground Task Force-Crisis Response-Central Command 16.1, prepare the hook block of a MAC-50 Crane to move Alaskan walls at Al Taqaddum Air Base, Iraq, Oct. 25, 2015. The 12-ton T-walls are placed around key structures to provide protection from shrapnel. - U.S. Marines with Engineer Company, Combat Logistics Battalion 1, and Marine Wing Support Squadron 372, currently deployed in support of Special Purpose Marine Air Ground Task Force-Crisis Response-Central Command 16.1, prepare the hook block of a MAC-50 Crane to move Alaskan walls at Al Taqaddum Air Base, Iraq, Oct. 25, 2015. The 12-ton T-walls are placed around key structures to provide protection from shrapnel.