The installation or changing the filter of a personal protective mask is done by opening the grey structure (the silicone structure does not come off during the filter change).
To make handling easier, we recommend pressing on the underside of the grey structure just below the valve: the lugs come off and it is possible to open the mask and take out the filter.
Once the new filter is installed, the bottom pins are first positioned on the bottom of the structure. The structure is then placed in its housing. The top pins are then positioned and "click" to lock the structure. These filters are compatible with a WAIR pollution mask or scarf.