| 摘要 |
An improved protective mask means and method of fabrication thereof wherein fold lines are formed in the facepiece along the facepiece centerline and between each lens and each filter means; the fold lines being formed by the lower edge of each lens positioned at substantially at 45 DEG angle adjacent to and parallel with the upper edge of the respective filter pocket means. The improved mask permits the manufacture of a mask which is lightweight and can be folded into a compact package.
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