Check the listing for details. Face Mask Round Dynamic Breathing Valves ( White ). Color: White, Condition: New with tags. Listed at 6.99 USD. Ship from USA!12 pieces Anti Dust Face Cover Mouth Filter Air Breathing DIY Filter Accessories - Breathing Face Cover Valves Dust-proof Wind-proof Foggy Haze Cover Filter.Anti-saliva, anti-smog, dust-proof, suitable for activated carbon.Works great for mask DIY.Simple installation, cut a hole in the mask, and press the breathing valve upwards. 1 Piece includes :Outer Cover (White) X 1Silicone Washer (Clear) X 1Inner Buckle (White) X 1 SPECIFICATIONSModel DynamicShape RoundMaterial ABSOdor resistant YesAnti-saliva YesAnti-smog YesDust-proof YesActivated carbon YesComfortable Yes Reusable YesWashable YesDesigned for fashion and sharper look Yes Ship from USA Yes Color WhiteWeight 2-g Outer Cover Diameter 38-mm Inner Buckle Diameter 38-mm Silicone Washer Diameter 28-mm Thickness 9-mm IN THE PACKAGEPack of 6 6 PiecesPack of 12 12 Pieces