1The internal design has a unique silencer function, the hollow pipe allows users to shout loudly still breathing smoothly.2The middle part of the bottleneck to grasp the comfort and thoughtful, the mouth of the arc can be completely wrapped in the mouth.3Bottle body can effectively prevent the sound leakage, the sound is only one-third of the original.4It is made of ABS, in line with the human bodys mechanics. Urban white-collar workers, feel pressure, screaming toward the drain pot, in order to decompression.5The edge of the bottle has a prominent dot, holding the bottleneck, keep the bulge in the bottom of the bottle position below the bottle mouth buckle the whole mouth, you can enjoy shouting vent.