Our Chicago search line bags are engineered with 1000 denier nylon covered on the back.  The bottom of the bag is covered with poly-coated nylon to resist abrasion, cuts and tears. All seams are triple sewn with a Tex 138 Nylon thread and comes standard with a breakaway adjustable shoulder strap and reflective trim. The large pocket on the back has 2 smaller pockets to hold hand tools or webbing for a jiffy harness.