Because outdoor travel bags are used in special environments, higher requirements are placed on the materials and processes of travel bags. All the stressed positions of the travel bag are stitched three times with stitches to make the stressed positions firm and durable. The buckle and other parts of the travel bag can be made anti-freezing, anti-smashing, and 120 degrees Celsius deformation without damage. The outer materials of the travel bag are mainly 420D Oxford nylon, 1000D nylon, 600D or 1000Dpolyester (polyester), or 1000D CORDVRA and other materials. The 1000D material has high density and wear resistance, which is very suitable for use in the field. CORDVRA is a famous high-grade wear-resistant nylon roving fabric developed by DuPont. The wear resistance of this material is much higher than that of ordinary nylon or polyester, and it is light in weight. More than 90% of the world's famous brand travel bags use this prestigious nylon material. These materials can withstand 0.5m~2m of water pressure to keep the contents of the bag dry. Some materials also have anti-tear function, once punctured, the rupture will not tear and expand. Canvas materials are also widely used in the manufacture of travel bags. The Canvas Republic is a typical example. Canvas is very popular because it is more durable, dense and rainproof, and its texture is very soft.