Multiply all by themselves? I have been using them but there were so many that I decided to sell them. I figured that 6 flat rate envelopes stuffed to the point of exploding would do the trick but NOOOO!! I filled 3 envelopes plus 2 lg. Flat rate boxes and there's still more. I think they are oozing out of the walls or maybe there are bunnies in my crumb box giving lessons. LOL!! :-)