Optigrün Protection and Drainage Board FKD 10 is used as drainage beneath frequently used pathways and on veal building mponents. CHARACTERISTICS MaterialRecycled HDPE (napped sheet) PP (fleece) Filter fleece PP thermally strengthened GRC 2 flow rate with 100 mm water lumn 75 l/m² x s mpressive strengthApprox. 400 kN/m² (40 t/m²) with 18% mpression (in