3 Layers Surgical Medical Mask Product executive standard: YY0469-2011 Dimensions: 17.5cm x 9.5cm Moderate Fluid Resistance: 120mmHg BFE > 99.4% Total Bacterial Colonies: 0 Synthetic blood penetration: 120mmHg Differential Pressure: <5.0mm H2O 16 CFR 1610 Flame Spread: Class 1 Testing Result: Level 2 Quantity per box: 50 pcs