The noise suppressors of the Series "R" come used for silenziare the culverts of the gas of drainage of the endothermic motors, the culverts of aspiration and drainage of the compressori of air to pistons or pumps of the empty "type Roots" etc.
The noise that is propaga along the culvert comes convogliato in the noise suppressor.
After to have crossed the reactive section that, thanks to risonatori details to multiple rooms, cancels the impulsive tones to lowland frequency, the gaseous flow crosses the dissipative section and supplies to attenuate the upper-middle frequencies.