4 x Pooter fart machines. Simple to make fart sound: put the free side up facing the palm of your hand, make the vent face about 2 - 3 cm behind the end of your thumb, and then press hard, finally you can hear the fart sound; In addition, you can also hear different fart sounds by adjusting the position and squeezing speed, and the effect will be better if you practice more.
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