[60921 Respirator Filters] – the professional half face respirator use a dual filtration system (filter cotton + activated carbon particles) to effectively block 97% of organic vapors/gases, pollen, dust and other particles in the air. Providing efficient protection against chlorine gas, chlorine dioxide, hydrogen chloride, sulfur dioxide, hydrogen fluoride, hydrogen sulfide, ammonia, methylamine, formaldehyde, and various types of particulate matter. [Use time] – The organic vapor filters can last for up to 220 hours of usage. When you feel that the breathing resistance is obviously too large, the human body feels uncomfortable, or the 60921 filter is dirty or damaged, the filter needs to be replaced. Whenever you smell something harmful, leave the work area immediately and go to a safe place to change the organic vapor filter cartridge. [Wide Application] – Our 60921 respirator cartridges can block multiple hazardous substances, work areas with chemicals, glass, metal, paint, agriculture, formaldehyde and other irritating vapors/gas. Protective against dust particles in mechanical work such as welding, sawing, woodworking, painting, grinding, graffiti etc. [High-Quality] – 60921 Particulate filters are made of highly electrostatic, non-woven, meltblown fabric, hot air cotton, activated carbon particles and high quality plastic shell, and filtering at least 99.97% of airborne particles. Please use with a breathing mask. Unit Count: 20.00 Count. Package Dimensions? 10.16 x 9.61 x 7.6 inches; 6.61 Pounds. Date First Available? October 13, 2023. Country of Origin? China. And we will work with you to resolve it to your satisfaction.