An optional manual release device assembly is available for MX 1230 and MX 200 Fire Extinguishing Systems. The manual release device fits onto the electric release device and is used to activate the cylinder valve, which in turn opens the extinguishing agent container to release extinguishing agent to the system. When a manual release device is installed, a pneumatically actuated limit switch (pressure switch) is required on the pipeline to indicate a release per NFPA 2001.