Feeke Five-layer Activated carbon PM2.5 filters and 6 Exhaust Valves Replacement, Active Carbon Filters for Mask (20)
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.
The package includes:
10/15/20/25/30/35 activated carbon
6x Exhaust Valves Replacement