Tenba T538 TriPak (634-513) 1050 Denier Ballistic Nylon Exterior tough as nails water and abrasion resistant yet light weight elegant and professional in appearance The finest hardware available including massive #10 YKK zippers welded steel D-rings and more Internal framework of corrugated, air channel polyethylene and high-density foam; provides structure, impact and puncture protection (selected styles) Rigid enough to ship, light enough to carry on location