5 pack bundle - total 50 pieces Extra protection for your loved ones with 3 ply medical surgical masks! Bacterial filtration efficiency (BFE) > 99% Clinically tested and certified Able to filter ash, dust and pollen Product structure: 2 layers non-woven fabric & middle layer meltblown filter material; adjustable nose clip and elastic band ear loop Useful life: 3 Years (Manufacturing year 2020)