Reusable Dust Face Mask with 3 Activated Carbon Filters - Personal Protective Breathable Mouth Face Covers - Adjustable Earloop - Washable - Cycling, Running, Woodworking, Outdoor Activities

BDTTBZ Reusable Dust Mask with Filter The steps about how to replaced the mask filter:1. Open the mask to expose the inside of the filter valve.2. According to the opening direction on the valve, turn the valve counterclockwise to separate the valve.3. Remove the filter.4. Replace with a new filter and rotate the valve clockwise according to the reverse steps above. Packing:1* Dust Mask2* Vent valve3* Filters Attention: 1. Mask is washable while filter pads are not, and it is advisable to replace a filter pad after using it for 4-5 days.2. Please insert filter pad into mask in the same way as shown in picture before using.