The BESTE series is a compact, integrated biofilm wastewater treatment solution designed for decentralized applications. Utilizing advanced A²/O-MBR and enhanced A³/O-MBBR processes, it ensures stable and compliant effluent even under fluctuating loads. Each unit treats 30–250 m³/day of domestic wastewater, serving approximately 250–2,000 people. Its modular plug-and-play design enables flexible expansion, rapid installation, and reduced land use and pipeline investment. Constructed from high-strength steel with a four-layer anti-corrosion coating, BESTE offers over 30 years of service life. The system is ideal for villages, tourist destinations, schools, hospitals, highway service areas, and temporary construction sites lacking centralized sewer networks.