In globalized production and R&D environments with stringent cleanliness requirements, such as pharmaceutical GMP workshops, biological laboratories, food clean filling areas, and electronic cleanrooms, the cross-border and cross-regional transfer of materials is a crucial link in preventing cross-contamination and ensuring product compliance. Pass box, as core auxiliary equipment connecting areas of different cleanliness levels (or clean and non-clean areas), become "invisible guardians" of the clean environment thanks to their precise isolation and purification design. While seemingly a simple "transfer box," it actually bears the important mission of maintaining clean pressure differentials, blocking the spread of contamination, and ensuring global industry compliance. Its design, selection, standardized use, and compliant adaptation directly determine the stability of the clean environment and the product's eligibility for international market access.