Ammunition output is usually counted in tonnes of explosive, numbers of shell bodies and lines of filling capacity. None of those measures says whether a completed round can still be accepted for service when one of its safety-critical components becomes unavailable, when a supplier changes a sub-component, when production moves to another site, or when a customer tries to qualify a second source. Fuzes and safety-and-arming devices sit exactly at that boundary between manufacturing and usable military output. They combine specialised production with configuration control, safety evidence, electronics or software in many designs, and a formal act of acceptance by a customer or safety authority. The question that matters for European rearmament is therefore not whether Europe has factories able to make objects called fuzes. It is whether European authorities and industrial actors hold the rights, the inputs, the qualified processes and the recognised evidence needed to sustain an accepted fuze configuration, or to replace it without creating a new dependency, and how much of that the public record allows anyone outside the contracts to establish.