Truma Frostair sound muffler for installing in the cold air system of air conditioning equipment for additional noise reduction in the living area.  You can make your cooling system even quieter by using Truma sound mufflers. Using just one reduces air flow noise within the interior by 50%. Using two reduces it by an amazing 90%!  Suitable for: Saphire compact, Saphire comfort, Saphire vario, predecessor model Frostair.