Main Body - SS, Inner Wheel - Copper, Stem - Brass. This is one of two ultra classic combos, the tri metal, with the other one being SS/Cu. I try to get a tri metal combo for every Billetspin top where it's possible and made in this combo. Generally Rich always tries to include this combo because it's so beloved. Awesome to have it in the Trigon like this, super rare, don't miss this opportunity!! I was lucky enough to get one of this combo into my collection during the original sale, otherwise I'd never be letting go of this one.