Yes, our reusable protective masks can be used without filters. We follow CDC’s recommendations on effective thread count for the best protection. The mask may feel a bit thinner but a thicker fabric does not automatically mean it’s a better mask. We use a fine thread (60/1) in high density (110x110 threads) to get the best result in protection with a cotton mask. In this way, we get a good and comfortable mask to wear and breathe through while providing a good filtration rate. The filters add significantly higher protection, it has a 99.19% Particle Filtration Efficiency (PFE) that can filter particles as small as 0.1 microns, however, the masks can be worn without the filters.