The MTA has hurricane storm covers for Subway entrances

Photo: MTA

I've never seen these before. The MTA just showed off this photo of Fiberglass and Flex-Gate stair covers for Subway entrances that would be deployed in the event that a hurricane or major storm brought heavy rains to stations flood-prone areas. I wonder how water-tight these are. Do they just allow for a slower leak instead of a torrential flood? So interesting...

A few more examples here.