The main body material is made of two strands of 315D Hollofil AirTM (66 nylon hollow fiber), both warp and weft, made in a certified factory that meets INVISTA's CORDURA® brand fabric production and quality standards. This is a fabric that has passed the CORDURA® brandfabric standards and has strength against friction, tearing, and fraying. The back is coated with PU and laminated with L-VENT®, a special moisture-permeable waterproof film, to further increase water resistance, and it has a 3-layer structure with tricot nylon laminated. MSPC PRODUCT's original fabric "MASTERTEX-08TM" combines durability, water resistance, and water repellency.The attached material is high-quality steer leather from North America, and a waterproofing agent made by "3M" is applied at the tanning stage. It is placed in a drum and penetrates into the leather. Afterwards, it is dyed and oiled to create a base, and the company's waterproofing agent is also sprayed during the finishing stage to further increase waterproofness. Waterproof, oil-proof, and stain-proof leather that has passed 3M's "SCOTCHGARD_" monitoring test. The test is performed even if the surface is scraped, so the effectiveness will not be diminished. The bottom and other materials are made of INVISTA's 1680D Cordura Ballis® Tech Nylon, which has approximately five times the abrasion and tear strength and durability of regular nylon, and PVC processing on the back improves further strength and waterproofness. I'm letting you do it. In addition, in terms of functionality, the shoulder harness cushion uses Outlast®, a temperature-regulating material developed for NASA personnel, and the mesh material is finer-grained and more textured than previously used materials. We use the best products. At the bottom of the front, we have placed an original tape that is woven into a loop of tape with slits made from reflective fabric to ensure safety at night.