Cassettes MBR are designed for the treatment of wastewater for obtaining a high quality effluent with minimal environmental impact. MBR cassettes consists of two parts: an upper casing constituted by a flat membranes and lower casing with air diffuser, that confine air both inside and ensure an ascending sweep flow. MBR system has also incorporated a diffused air system and a permeate collector where all permeate filtrated by each flat membranes is discharged. The membranes are placed on frame made of stainless steel. Permeate of each membrane passes through a silicone tube and is collected in PVC manifold. System is designed for easy inspection and placement guide system. The average production of the different models ranges from 12 m3/day to 160 m3/day in urban wastewater and membranes surfaces from 30m2 to 400m2.