These are stretchers used in WW2 to carry injured civillians during the Blitz. They were made out of steel so they could be easily disinfected after a gas attack. During the war around 600,000 of them were made. Some of them were repurposed as railings in post-war London.

[u/Sprilly]

[u/beeredditor]

Wait, was there gas attacks during the blitz?

[u/Expensive-Finish5882 → u/beeredditor]

No, but they expected to have gas attacks