Set of 10 Activated Carbon N99 PM2.5 Filters and 4 Exhaust Valves Replacement, Active Carbon Filters for Mesh or Neoprene Mask

Description

Size:Set of 10 DURATION OF FILTERS AND VALVES Duration time for filters depends on the pollution level and the frequency of usage. We recommend replacing the filter once a week if the mask is used extensively.  The valves should be replaced when they get damaged.  Package Include: 10 Activated Carbon 4 Exhaust Valves Replacement