CCW MiraDRAIN GR9400 is a high-capacity retention/drainage composite consisting of a three-dimensional, high impact polystyrene core with holes allowing proper water retention management and drainage. A moisture retention mat fabric is bonded to the retention side of the molded core. The moisture retention mat fabric also serves as a filter medium to prevent the passage of particles into the water reservoirs while allowing excess water to pass freely into the drainage system. MiraDRAIN GR9400 is designed for use in horizontal green roof or large planter applications.