Portable acoustical shell structure

Portable acoustical shield and sound enhancing closure

Protecting system for roadway adjacent areas

Pulse converting exhaust silencing system

Rotary flow muffler

Self-cleaning muffler for an abrasive blast system

Silencer element

Silencer for a heat engine

Silencer for combustion engines

Silencer for ventilation ducts

Silencers

Silencing device for internal combustion engines

Snowmobile muffler

Sound absorber

Sound absorption with variable acoustic resistance means

Sound absorption with variable acoustic resistance means by osci

Sound attenuating engine enclosure

Sound deadening laminate

Sound insulating hoods for noise emitting apparatus

Sound reducing enclosing