My K-27 #461 in HOn3 is finished

[Graffen]

I've finished the Sunset models K-27 as number 461.
It has a Tsunami decoder installed.
I painted it with a green boiler just because....


Here's my collection of K-27's:

#452, 455, 460, 461 and 463.
One of these are not like the others though. As one isn't a brass engine.
Which one?