"KN95" is the standard GB2626-2006 for respiratory protection articles published by the State Administration of Quality Supervision, Inspection and Quarantine and the State Standardization Administration, and is not a specific product name. As long as it meets the KN95 standard and passes the standard of respiratory protective equipment GB2626-2006, it can be called "KN95 mask".
In GB2626-2006, KN95 is the standard for dust protection, which is cheap and easy to be adopted by relevant dust industries. N95 mask is used for occupational respiratory protection, including some dust particles (such as dust, smoke and other non-oily particles).
The biggest characteristic of KN95 mask is that it can prevent droplet infection caused by body fluid or blood spatter of patients. The size of the droplets is 1 to 5 microns in diameter. U.S. Occupational Safety and Health Administration (OSHA) requires personnel exposed to tuberculosis germs to wear masks above N95 standard for institutions.