KF stands for "Korean Filter", and 94 stands for Bacteria Filter efficiency of Mask to 94%. We can tell its the Korean Version of N95 Face Mask. Differences lies in Distinct 3D Design.
KF94 is worn by public as a protective gear to prevent Covid or to safeguard from Pollution and other environmental allergens. They are better to 3 Ply Face Mask in terms of Bacteria Filtering Efficiency.