The Mirro Pressure Cooker Metal Safety Fuse, Part Number S 9888 is a feature on some Mirro pressure cookers to prevent you from being injured as a result to a high heat pressure problem.
Part # S-9888
For Mirro Pressure Cooker models:
M-0312-35, M-0406, M-0512, M-0522, M-0526, M-0622, M-0294-37, M-0294-39, M-0294-50,
M-0296, M-0394, M-0396, M-0398, M-0404-35, M-0404-37, M-0404-39, M-0436-35, M-0436-37,
M-0436-39, M-0494-35, M-0494-37, M-0498-35, M-0534, M-0536, M-0594, M-0594-35, M-0594-37, M-0596, M-0596-35, M-0596-37, M-0596-39, M-0598
The metal safety valve is designed as a built in safety feature in the lid of your pressure cooker. Made of a special metal alloy that is sensitive to high heat levels.
In the event that the pressure cooker is neglected, the metal safety fuse contains an alloy pellet which will melt away causing excess pressure to be released.
Once the pellet melts away, you will need to replace the safety fuse with a new one. This metal safety plug has been since replaced with a more efficient safety feature in modern pressure cookers.
There’s a slight chance that you will need to replace your pressure cooker lid if you are unable to remove the safety plug.
We suggest that you make an attempt to gently remove the plug without damaging your pressure cooker’s lid. Once you have it removed, simply order a new safety fuse. You may want to have multiple on hand. If you are not able to remove the plug you will need to have the pressure cooker lid replaced. You then may want to consider replacing with a new modern pressure cooker with the newer safety feature designs.