It's fake!
They are all fake!
After dismantling them, the brought Geiger counters were completely useless.
What real nuclear warheads would be like this?
Besides the cryptographic and self-lock mechanisms, inside there should be a heavy metal enclosed warhead.
From top to bottom, the warhead consists of a small nuclear bomb for detonation, polystyrene foam and an aluminum box for regular isolation and protection, and at the bottom, lithium deuteride and plutonium rods enclosed by a protective shell, with many neutron generators inside the plutonium rods.
This design is based on the principle of explosion.
At the moment of detonation, the small nuclear bomb produces a great amount of radiation, heat, and blast energy.
While heating and compressing the lithium deuteride, it also makes the plutonium rods bend and deform, allowing the neutron generators to release a large amount of neutrons.