My late Fatherís Super Ikonta 513/2 folder had developed two pin holes in the corners. Tried to get a new set of bellows but itís basically not doable. A repair man suggested using this stuff, he thins it down and allows it to be absorbed into the material inside the bellows, using three or four applications.
It works beautifully, it has been absorbed and has created a complete light cover over the pin holes that were there.
So here is the stuff if anyone has a similar issue now or down the road.