Mask4Aide melt-blown* disposable mask filters add 3 Layers of filtering protection. the iFilter adheres and fits into most masks. The package contains 10 filters to a pack. Each filter has 20 adhesive stickers on the back to apply inside yourMask4Aide iMask.Mask4Aide melt-blown* disposable mask filters add 3 Layers of filtering protection. the iFilter adheres and fits into most masks. The package contains 10 filters to a pack. Each filter has 20 adhesive stickers on the back to apply inside yourMask4Aide iMask.Mask Dimensions: 4" x 3" x .25".Features: 20 adhesive stickers to securely stick to the inside of the mask 10 pieces per pack Wear comfortably for hours at a time One size fits most masks Breathable Odor resistant Not handmade These masks are not FDA Approved. *Please note these are not a replacement for medical-grade N95 masks or PPE, but are meant to bridge the gap.