FIT & DESIGN 30 pack of replacement filters designed specifically for the BUFF® Filter Mask Non-reusable, disposable filters Highly breathable to provide comfort throughout the day 3-layer filter construction provides 98% bacterial filtration efficiency and water resistant properties Each filter can be used for a maximum of 24 hours Filter life may vary based on usage and environment ADDITIONAL DETAILS Not intended for medical use Packed and sealed in a clean, sterile environment