AT targets what Defiance believes is the most critical and supply-constrained layer of the humanoid robotics buildout: the actuators. Mechanically, a humanoid robot is a collection of actuators, every joint requires a motor, gearbox, encoder, and controller working as a single unit, and a full-body humanoid carries dozens of them. Yet the actuator supplier ecosystem remains among the least developed in the entire robotics hardware stack. The compact strain-wave gearboxes essential to humanoid joints are produced by a small number of highly specialized manufacturers, with production processes that are precision-bound and capital-intensive. The ETF seeks to track an index composed of 25 companies deriving at least 50% of revenues from various actuator systems. The index is reconstituted and rebalanced quarterly.