Reusable High Efficiency Filter - Pack of 4 (Medium)

idMASK filters consist of 3 separate layers designed to filter dangerous particles from the air. The high-efficiency electrostatic layer filters particles from PM2.5 all the way down to PM0.3 with very little air resistance. It is engineered for low resistance N90 filter and easy breathability. These filters lasts 4 to 6 weeks if used 1 hour daily for cardio-vascular activity. Kids can now breathe comfortably while wearing the mask. The box contains 4 filters.