The Gibson MWA round race Muffler delivers Maximum Sound and the Best Muffler Flow PERIOD in a 5.0 in. compact competition ready package! This Straight-thru design promotes exhaust gases to flow at the highest rates flowing only 3cfm less than a 3-in. straight pipe, improving power potential while keeping interior drone to a minimum. The MWA muffler has NO internal packing or weak baffles, allowing it to maintain a lightweight design with a unique and powerful sound. The MWA muffler is 100% Made in the USA and is constructed of high quality Stainless Steel to outlast the competition. When it's time to make your Hot Rod, Race Car or Off-Road toy, sound and perform as good as it looks, there is no better choice than Gibson's MWA Race Muffler With Attitude.