Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: What is the diameter of this gasket?
Document: The gasket (item 12-22QTPress Cook Gasket) purchased from Amazon arrived timely but, it was too big in diameter and too thin. I followed the directions to soak it in hot water for 15 minutes. Then I dried it and put a thin coat of cooking oil on it as instructed. When I put the gasket in the pressure cooker lid it buckled badly but, I spread the buckles around as uniformly as I could.
It didn't seal as tight as the original gasket but did the job, although it took longer to build pressure..
My family has started doing more canning and like to have an extra gasket on hand in case we need it. Fits great! !
The old gasket on our caner had pretty well rotted and cracked. The new one fits perfect and we are safely canning again.
I bought this gasket as a replacement for my pressure cooker's original gasket, worked great, got me back up canning quickly!
product description obviously does not match the product. This is a gasket for a pressure cooker, not a pan. Will it fit a vintage Mirro pressure cooker model M0512?
For 12 & 16 qt. MO406, 22 qt. MO622, MO526, & MO522 cannersthis Gasket is way too small for the Mo526, have to send it back
This gasket fits an old Mirro canner that I've used for over 30 years. Nice to know I don't have to run all over the country trying to find a gasket.
Product was exactly what I needed. Restored our canner to great working order. Did not know how worn our old gasket had become until we uded the new one.
Ordered two of this item. One gasket was in a plastic bag and the correct one. The other was loose in the box and was not the correct gasket. Was much smaller and for a different cooker.
Answer: Having the gasket installed in the lid as it would be for use, I measure the gasket right at 14 inches.  That is from inside lip to inside lip of the lid.  I see no other way to give even a reasonable answer. The gasket fits as it should even being a bit tight as compared to the old gasket, which is how old I have no idea. It works well as tested.  I pressured it for 15 minutes @ 15 psi setting but not under actual canning procedure.  See my review for model of cooker I am using.