Pierceable cartridges can't be disconnected once they've been pluggedinto an appliance, so they're suitable for more intensive or longer use they're also our most economical and widely available cartridges. TheC206 GLS cartridge has a new integrated flow reducing system, the GasLock System, which is compliant to the new European standard EN 417:2012legislation. The system prevents the majority of residual gas fromescaping the cartridge when accidentally disconnecting it from theappliance, thereby also preventing flare-ups.