You can trust these medical-quality face masks will live up to your expectations. In addition; no worries about extended lead times or overseas freight issues, besides they are made right here in the United States. Along with a three-layer construction, these quality masks have an ASTM International (formerly American Society for Testing and Materials) rating of ASTM Level 3, a BFE (Bacterial Filtration Efficiency) rating of 99.5%, and a Delta P (Breathability) Rating of 3.5 – 3.7. Latex-free, lightweight and soft, with foam-based ear straps that are easy on the delicate skin around the ears. Simply slip straps over the ears, lightly press along the nose piece to fit, and adjust the mask to cover the nose to the jaw. Our masks are disposable and are for single use only. One size fits most.