At first I attempted to silence glass wool and mute it, but when I tried the engine, there was no change in the rain. In this way I thought that it was a trouble in the neighborhood, and I purchased this product to silently sound momentarily. The result got quite quiet. I think it is more quiet than a normal muffler. Those who are suffering from the silence of the super trap are wrong with this product. Installation is also easy and it is saved.