The C2 is Siltrax's 3kW closed-cathode, air-cooled fuel cell stack, engineered for weight-sensitive applications such as UAVs and off-grid energy systems. Its closed-cathode architecture rejects stack heat directly cooling channels, eliminating the weight, volume and complexity of a separate liquid-cooling circuit. A dedicated pathway separates cooling from oxidant distribution, shielding the catalyst from external air contaminants while delivering sufficient airflow to protect the membrane, ensuring durability and performance advantages over traditional open-cathode designs. A dead-end anode architecture further supports efficient hydrogen utilization and simplified fuel management without continuous anode recirculation.