Abstract: A fire suppression device characterized by a plunger that is extendible from a housing for delivery of a fire suppressant foam. The plunger may be equipped at its outer end with a puncture tip that can penetrate through the wall of a container or cargo cover for delivery of the fire suppressant foam directly to the cargo, preferably after full or almost full extension of the plunger. The plunger may be driven outwardly under high force by a pressurized gas that may also be used as a propellant for mixing with a liquid foaming agent, preferably within a foaming chamber carried by the piston. Provision may also be made for connection to a source of pressurized fluid to effect retraction of the plunger.