Sanfiland New 3D Cutting PM 2.5 Activated Carbon Filter Insert, 5 layers Pm 2.5 Filter Replaceable Protective Filter to Anti Haze Dustproof Air Pollution Large Size (100)

Fit well and are useful under cloth masks.

I've used these for a couple years inside of my cloth masks and have been much more comfortable than the flat options. I've been staying healthy using them too.

Masks make my nose itch, but these don't! They also seem less steamy. I like.

Although not perfect, they work pretty good for the Oakley Msk Mask. The Oakley replacements cost about $10 for 3. These are a lot more economical and they cover all exposed mesh on the Oakley Msk Mask.

We have reorder these a couple of times because we love how the shape actually fits over the nose in cloth masks. Most are just rectangular. They actually help the cloth masks from sucking into your mouth when talking and breathing too.