The fire extinguisher has been "miniaturized" to the size of a biscuit. Passive and uncontrolled, it is automatically triggered by temperature. Upon the onset of fire, it automatically releases flame-retardant gas and fire-extinguishing free radicals, extinguishing initial fires in a 0.2 m³ space within 6 seconds and rapidly depleting oxygen to inhibit reignition. Its performance remains undiminished after being submerged in 1 meter of water for 24 hours (extinguishing fires within 8 seconds), and it remains reliable even in humid or condensation-prone environments such as electrical cabinets. With an ultra-thin profile of ≤10 mm and multiple mounting options, it can be easily installed in cable connector housings, terminal boxes, or inside charging piles – wherever there is a fire ignition point, install one.