The $32 billion Minnesota conglomerate 3M is one of the world’s largest manufacturers of N95 filtering face masks, which have been in high demand in the U.S. and around the world since the coronavirus outbreak.

N95 respirators are so named because they are capable of filtering out 95% of large and small particles, including certain types of bacteria.

They are considered essential equipment in occupations ranging from construction to medicine.

And in early 2020 health officials worried there were not nearly enough of them. In early March, officials from the U.S. Department of Health and Human Services said the country had only about 35 million of the 3.5 billion N95 respirators needed in the event of a full-blown pandemic.

3M doubled global production to 1.1 billion per year from about 400 million per year, and the company said in late March it plans to double production again to 2 billion within 12 months.

The explosion of face mask demand could provide a small boost for 3M, which reported sales of about $32 billion in 2019. The company does not break down the actual size of its face mask business, but some Wall Street analysts estimate 3M sold anywhere from $100 million to $325 million in face masks prior to the outbreak of the disease. The outbreak could add another $300 million in sales, said one analyst.

This would be only a tiny portion of 3M’s overall business, but the importance of the product still has focused a tremendous amount of attention on the company.

Shares of 3M, which are valued at about $78 billion, have fallen more than 22% since the start of the year.