Buff is a product from the www.buffusa.com . Please look there for further product information. I am very pleased with the two that I own. These light weight tubular microfiber polyester found a new purpose during my spring rides.
Spring things in the air bother my allergies and breathing. I typically had used the buff around my head to cover the mouth and warm the air going into my lungs. As the air warmed up , I would pull down the buff, but this year I kept it up. Because the air was warmer I could pull the buff even over my nose and not have to worry about foggy glasses.
After several rides I do find that the buff as an air filter has helped. I have not had to deal with a bugs flying in my throat or other airborne irritants causing problems. The material provides warmth on cool days, but it has not been uncomfortable on hot days.