Rectangular resistive muffler: ● for ventilation systems, and ventilation pipe through the flange connecting directly to facilitate the installation; ● through rigorous calculation of the acoustic and aerodynamic, with minimum ventilation resistance and regeneration of noise to achieve precise control of noise; ● can be installed in series of different models to achieve a better performance requirements; ● Depending on the installation conditions, noise reduction requirements, the sound source spectral characteristics of the different resistance and other factors can provide other models for choice; ● production of materials can be installed for different conditions and cleanliness requires a flexible choice;