"Keep this bag - you might need it!" This lovely old-fashioned brown bag contains a repair patch for raincoats or such. Made of fabric-coated silver colored rubber. Probably from the '60s or something, but still functional we dare say. One-off lot!
It says you should use rubber glue (for example the stuff used with bicycle patches) to apply the patch. The best way is to add the patch to the inside face of the torn fabric, with the rubber side facing the coat. Rough up the rubber side of the patch a little with sandpaper, then add rubber glue on the patch and the place to be patched. Let dry for just a moment and press them hard together. Can also be sewn on with the obvious disadvantages of losing full waterproofness. This is pretty much the whole thing written on the package.
You'll get a random shape patch. These are probably factory leftovers so they come in all shapes.
Made by Nokia! The old proper one!
And it would be a tad weird if these were used.