100Pcs Adult PM 2.5 Activated Carbon Filter Insert 5 Layers Replaceable Anti Haze Masks Filter Paper (100 Pack)

Fit into my cloth masks perfectly, do their job just fine. Filter air particles like they should, which I can actually prove as I know a guy who's a lab technician and asked him to test an old one for me.

I bought these as replacements that came with a Fortress company mask. While they look similar, these are slightly bigger and do not sit as well inside the filter pockets. I also find they are very thin compared to the others. You hold it up to the light and you see far more light filtering in that you do with thicker versions.

The filters arrived on time and fit well into all of my masks. I even opened up some masks that had double layers but no place to insert a filter and they worked well there too. It makes me feel safer to have a filter inside my masks and I'm also doing my part to make it safer for others. I filled all of my masks so that I could just grab and go whenever I needed one. No odor and breathing is no problem. I even tried to blow out a candle with a filter in my mask and couldn't do it!

The price is great, got what was in the picture and description and fast delivery!

These filters are awesome, I don’t even feel them in my mask! And they are very easy to slide in the mask pocket, in fact I didn’t realize most of my masks already have pockets so I didn’t have to go buy more. Buy them, you will not be disappointed!! ❤️

Going through filters daily, needed to keep a good supply. Good value and arrived next day.

They fit in my face mask pocket perfectly! I am so glad I got these filters!

Much thinner than others I've purchased in the past. A tad smaller too. The good is the price but you get what you pay for. I use these in my cloth mask combined with a 4 ply surgical mask. I would not recommend to use alone as it's very thin as a stand alone.