After a fall with a Spark Airbag body protector, the gas cartridge must be replaced. The used cartridge can be unscrewed without any risk. The vest will have to be reset. CO2 cartridge is welded shut. Any used cartridge must imperatively be replaced with an identical new one. Cartridge size must be compatible with vest size: for XXXS size vests = 38g cartridges. For XXS and XS sizes = 45g cartridges. For S and M sizes = 50g cartridges. For L and XL sizes = 74g cartridges. For single use only. Composition: cast steel and CO2. Instructions: handle with care, do not throw around. Once used, dispose of them in a recycling bin intended for metal.