发动机排气消声器根据其结构可分为抗式、阻式、阻抗结合式，怡允环境可根据客户提供的机型、应用及降噪要求等信息对产品进行计算、选型、和设计，合理设计可提供给客户工业级、住宅级、临界级、医院级和级消声器。

Engine exhaust silencer according to its structure can be divided, reactive, absorptive and  combines .emission-tech can provide customers information with a model, application and noise reduction requirements, calculation, selection, and design ,Industry grade, Commercial grade, Critical grade,  Hospital grade and Ultra-quiet grade silencers can be provided by Emission-tech.