According to today's papers, while it is made in US, it's made in several versions. The cheaper, non-fireproof version used in the Grenfull Tower is banned for use in any tall buildings in the US, because of fire risk. It's banned also in various other countries. But it"s not banned in the UK, because calls for it to be banned.

Using the fireproof version of the material would have cost about another £5000 for this building.