Weston, Colo. native Staff Sgt. Jon Waldron of the 15th Transportation Company, 165th Combat Sustainment Support Battalion, 1st Sustainment Brigade guides a barrier into place at Joint Security Station Ur, a barrier holding yard in Sadr City. Barriers such as this one are being used all over Baghdad to build solid walls of reinforced concrete. The 165th has moved over 20,000 such barriers since their arrival in April.