Comment by questionableans

Under $100: Reusable respirator masks + P100 replacement filters.

They were harder to get earlier in the pandemic, so I bought a less popular brand in addition to the popular brand one I already had from a repair project.

Reasonably comfortable, and I haven’t had a single respiratory illness since I started wearing them when going out. Also good for allergies, smoke, keeping my face from freezing in the winter, and looking like I’m in a SciFi movie.