Because backpacks are used in special environments, higher requirements are placed on the materials and processes of backpacks. The position of all the backpacks is sewn with sewing thread to the sewing machine three times, so that the force position is strong and durable. The components such as the buckle of the backpack can be used for anti-freezing, anti-tampering and 120 degrees Celsius deformation without damage. The outer material of the backpack is mainly 420D Oxford nylon, 1000D nylon, 600D or 1000D polyester (polyester), or 1000D CORDVRA and other materials. 1000D material is high density, very wear-resistant and is suitable for use in the field. CORDVRA is a very famous high-grade wearable nylon roving fabric developed by DuPont. The material's abrasion resistance is much higher than that of ordinary nylon or polyester, and its light weight. More than 90% of the world famous backpacks use this prestigious nylon material. These materials can withstand water pressure of 0.5m~2m to keep the objects in the package dry. Some materials also have a tear-proof function. Once pierced, the tear will not tear open and expand. For more information, please pay attention to China Backpacking Network