JBL Combibloc II is a set of high-quality foam pads with various pore sizes for the JBL Combi Filter basket II. The large-pored pad serves as mechanical large-area pre-filter material for the upper part of the combi filter basket II. Due to the T-Profil cut it reliably catches large dirt particles at optimum flow capacity. This way the biological filter materials underneath are protected against unnecessary soiling. The fine-pored pad in the lower part catches any dirt particles which could damage the pump, while filtering biologically.JBL Combibloc II+ filter inserts for the JBL Combi filter basket II+ 2 pads 15 PPI, 1 pad 35 PPI+ for JBL CristalProfi greenline e402, e702, e902+ for JBL CristalProfi greenline e1502, e1902