Mask filter (PM 2.5) is made of non-woven protective layers (moisture-proof and breathable) with a layer of activated carbon insulation in between. Insert a filter into your mask for added protection. The filters are disposable and recommended for 1-3 days usage.
 
Filter size for adult : 12cm x 8cm
Filter size for children : 10cm x 7cm
 
NOTE : Filters are imported from China with claims of being 5 layers each. We do not guarantee the efficacy of the filters.