Set of 2: One for you and one for a friend in need! Great for running, biking and travel. Use in schools, colleges, and offices for staff and visitors. Size: One size fits most adults. Material: Triple-layer protection. Recycled polyester, melt-blown fabric, 100% cotton. Purpose: To protect you from germs, smoke, pollutants, droplets, bacteria, dust, toxins. Features: washable, reusable 95% bacterial protection. Dust resistant, splash resistant. This mask is not a replacement for surgical-grade personal protection and has not been reviewed, cleared or approved by FDA for the said purpose.