1、Meters
2、Pressure Regulators
3、Control Valves
4、....

　·Tolerance to extreme surface finishing conditions, such as "ascast".
　·Conformable toflanges with higher"out-of-flatness" values, such as stamped steel and plastic covers.
　·Lower bolt torques possible.
　·Fewer fasteners in the system.
　·Smaller or lower grade fasteners..
　·Allows for components with less mass and more distortion.
　·Easy to fabricate.
　·Good chemical compability with burning gases with very low gas permeability.
　·Very low side-flow improving crush-out resistance