Discontinued for now:
Some sources state that the cracker is the portion of the whip that makes the loud noise known as the sonic boom, but this is misleading. A whip without a cracker will still make a sonic boom, but it will be less audible unless you are standing directly in front of it. The cracker functions to disperse the sound so it can be heard more easily.
Our older poppers I made were just plain nylon mason twine, but newer ones are made from tarred nylon drop line that’s most often used for catching catfish. This twine is very tough and makes a long lasting popper that is harder to break and gives a nice loud crack as well.