Big O Tire on Kingsway patches sidewalls...but how?
 

Got my tires from there years back, great service.

I noticed that they have a sign that says they repair sidewalls. Everything I find on the internet says not to do that. But I talked to them and they say they have a special method, and they advertise it pretty proudly on a sign in the front window.

So...how? Is there really a patch that can do this?

Not only should it not be done, it is absolutely NOT road legal, nor should it be legal for them to provide that service to the public