Grease filters should be replaced regularlyAs the filters trap the grease from the air they will become blocked over timeIf the filters are filled with greasy residue your cooker hood won\'t work as efficientlyPlease check below for the list of compatible cooker hoodsImage for illustration purposes only . Small grease filter type B for selected electriQ cooker hoods you will also need to purchase a large grease filter eIQAL03D690B . 13.5cm * 39.9cm Dims Compatible with . eIQCHB90B.