Sub-efficient filters include sub-high efficiency filters and non-barrier sub-efficient filters;
There are sub-high efficiency filter including GK (with sub-sub-high efficiency filter), GKW (high temperature sub-efficient filter), GKA (high humidity sub-efficient filter);
GKYC (sub-high efficiency filter), GKYC (sub-high efficiency filter tank), GKYL (ultra-low resistance without partitions), GKYW (sub-high efficiency filter without partition) Sub-high efficiency filter), GKYD (knife-shelf type without sub-efficient filter)