At the Lincoln MRC show in Newark this past weekend, I bought a bottle of Carr's Steel/White Metal blackener, and a bottle of the Brass blackener, and to be honest, I wish I hadn't bothered as results were disappointing to say the least. Despite being applied to cleaned components, and in one case, immersing a bogie into the solution, the nearest I got was a slight brown tinge akin to a thinned wash of murky brown paint. At £9 a bottle and mediocre results, (and that's being kind!), I'll stick to paint in future. Keith.