On Saturday, 29 August 2020 13:13:32 UTC+1, David WE Roberts (Google) wrote:
I want a screw down window stay in bright metal (that is, SS, chrome,
brass not black) which is as long as possible. Over 300 mm but longer is
better.

12" brass here

https://www.doorhandlecompany.co.uk/...12-poli-27871/

There are longer door stays, but they fail your appearance criteria.

https://www.ironmongerydirect.co.uk/...-silver-866596

This is shorter, but more substantial?

https://www.ironmongerydirect.co.uk/...d-brass-699058

Owain