32 Bubble Holes】According to Aerodynamics principle. While the powerful fan works, it will create a strong wind to make the bubbles come out from the 32.Our Bubble Machine designed from unique Gatling appearance. The two handle design is conform to the Ergonomics Eco-friendly, safe and durable. The Machine Bubble Rocket Boom is made of safe and good quality ABS material. It is Eco-friendly, safe and durable.