The 3M 8812 mask is a lightweight, effective, comfortable and hygienic respiratory protection against particulate matter. The convex shape, double headbands, nose pad and steel nose clip guarantee a good seal for most face shapes. The unique exhalation valve and foldable filter ensure comfortable protection, especially in hot and humid environments. The 3M 8812 does not require costly and time-consuming maintenance. So this mask is literally maintenance-free.