MERV 16 Filter Material, Filter Mask Insert Triple Layered Protection Nonwoven Polypropylene & Nanofiber, Efficiency Breathable DIY Design Media Roll, Easy to Cut Any Size

This stuff is a little bit thinner than a 2.5M filter and it's definitely a bit stiffer, which is great because it helps your masks keep its shape. Well, it's great for me anyway. I have three different types of masks, and it works well in all of them. I absolutely do not understand what the hell these people are talking about when they say you can't breathe through it! You can definitely, easily breathe through it. Maybe they're used to having masks without a filter at all. Or a cheap dollar store or grocery store cloth mask that you pick up for $2.50. Or something like that, because there's no way in hell that you can't breathe through this. To me, this is a bit more breathable than a 2.5M filter which is barely anything in the first place. You cut it so it fits your masks just right. If you've ever had a mask with a removable filter, the only difference here is that you get better protection, you can barely tell it's there, honestly. If someone says that it makes it difficult for them to breathe or that it interferes with their breathing, then the issue is with them physically, not with this product! Seriously.

Not easy to i stall but I used it somehow, I like how it’s filtering the air. Feels good

I live in a very heavy traffic section of Manhattan. The dust that collects on my window sill is over the top and my air purifier works well, but must be cleaned frequently. Additionally I have allergies and wanted to reduce the allergens coming through the window.I purchased adjustable window screens and hot glued this filter to it to stop the particulants at the window. My air purifier is far less dirty.

The roll is the perfect size to work with cloth face masks. Material is breathable and provides some shaping for DIY cloth masks.

This is no way merv 16

Ordered masks with a filter pocket and then ordered the Merv 16 filter material to place in the pocket. Carefully measured the pocket dimensions and cut out filters for the masks, being careful to get the largest filter size possible to fit into the pocket. A bit tedious to get the filter in and situated. Just takes a bit of patience.

Great filtering, but very low flow rate.

This is why the 4 stars, tried to use it with a Merv 13 filter, it restricted too much air flow thru the furnance. But it is what they say it is.