According to one aspect, a fire extinguisher includes a fire extinguisher reservoir and a fire extinguisher outlet burst disc that forms a discharge barrier between the fire extinguisher reservoir and a discharge head to retain a pressurized fire extinguishing agent at an internal fire extinguisher pressure within the fire extinguisher reservoir. A cutter is detained within the fire extinguisher proximate the fire extinguisher outlet burst disc. An interior container within the fire extinguisher reservoir has a container pressure and is sealed with a container burst disc. An activation device having a piercing member is operable to pierce the container burst disc and diffuse the container pressure to create a pressure differential relative to the internal fire extinguisher pressure at the cutter, thereby driving the cutter through the fire extinguisher outlet burst disc to release the pressurized fire extinguishing agent through the discharge head.