I have used 3M mask in the past, but I tried this product at about 10% cheaper. Since the nose stop is plastic, it opens during use and creates a space between the nose and the mask. This is also seen in 3M products, I think that plastic is useless. It is said that it takes time and effort to separate the metal, but it is better than breathing dust and dust. I have regret feeling irritability in my throat. However, I have a nostrils because of it. Otherwise please do.