The Biden administration will announce Wednesday that 400 million non-surgical N95 masks will be made available to the public for free at thousands of "convenient locations" across the U.S.

Why it matters: This is the largest deployment of personal protective equipment in U.S. history, according to a White House official. The masks are slated to be available at numerous local pharmacies.

• The Biden administration announced its intent to distribute masks nationwide last week amid mounting criticism over its response to the pandemic.
• The administration will begin shipping the masks this week, and they are slated to be available at pharmacies and other locations next week.

What they're saying: "This historic step builds on the significant actions the Biden Administration has already taken to increase ... access to masks," a White House official told reporters.

• The administration "has and will continue to make masks available for health care and other essential workers through states."

The backdrop: Several Democratic lawmakers have urged the Biden administration to purchase and distribute domestically manufactured KN95 masks to any American household requesting them.

• Last week, Sen. Bernie Sanders (I-Vt.) introduced a bill to provide every person in the U.S. with three free N95 masks.