Wearing a cloth mask does reduce the risk of spread, but to get the most out of your face covering, add a filter. Profound's PM2.5 Replacement Filers shield your face with a five-layer design that includes two layers of filter fabric, a double layer of non-woven fabric, and an activated carbon fabric. Made from materials used in respirators like the N95 and KN95, they can minimize airborne particulates by up to 90% when inserted into a mask. Each package comes with 10 filter replacements.