Coldrail Blind Courier Beacon

Coldfrail’s courier beacon rides inside a freezer token, the thick coin used to reserve refrigerated cargo drawers. Its transmitter stays asleep until the temperature drops below freezing, then emits a narrow packet through the drawer’s own telemetry antenna. The courier only has to place it in cold storage and walk away. Delivery may take hours, depending on the freight cycle. Warm inspection reveals an inert token with convincing wear. Unfortunately, repeated thawing warps the battery and sometimes makes it transmit early—from a pocket, a tram seat, or the security queue. The stall sells insulated pouches separately. Of course it does.