Pre cut non woven filter replacement for mask

⚡MASK FILTER Made out of non woven FILTER with over 90% EFFICIENCY Extra thin layer which make it very easy to breath under your layers of fabric mask. PET (Polyethylene Terephthalate) 99% Quantity: 25pcs Size: 5x4 inch pre cut (you can cut them the size and shape you like at home ✔️ Tested with aerosol at inhalation flow rates of 95 liters/min with particle size was 0.6 micrometer ✔️Certificate of laboratory for filtration efficiency and safe from toxic substance test available on demand