I don't know exactly what this is - but it doesn't matter. Superb rendering of the crisp white, solid blacks. and the metal tones in between. Sepia works very well.
Take this for what it is worth, as this is nice as is. For my taste, I think you need more light in the back (black area.) The front area is absolutely perfectly lit.
Wonderfull image. I love the silky sheen of the cranks, (is that the right word?). Focussing a DOF are spot on. Fits the challenge very well. The colour sets if off very well. I think if anything I would have tried cropping more of he dark area at the top, perhaps as far down as just above the unpainted main bearing. Very well done.