Checking balance for sparklet gas cartridges between 39 and 43gm full weight, for powering fire extinguishers

This device is used to check the weight of the gas cartridge used to power some fire extinguishers in order to confirm it is full and working. A fire extinguisher powered by gas cartridge relies on pressurisation. The extinguisher is un-pressurised until it is in operation, when the ‘sparklet’ gas cylinder pressurises the extinguisher, providing power.