For use with the Gas-O-Matic®, these replacement sphincters are available to replace worn out sphincters due to age and continual use.  Each package contains two replacement sphincters made using high quality, high tech, vinyl coated stainless steel and durable polycarbonate plastic center, with 100% silicone high speed bands. These sphincters were scientifically engineered using Sphysics (Sphincter Science and Physics) to provide you with the most authentic flatulent sounds.