The 80db SPO mufflers are certified compliant to the EPA requirement of 80db noise level when installed on a 2007 or later Harley-Davidson® touring bike with a stock 96 inch engine. It says so right on the muffler. Use on other engine configurations are not covered by this certification.
What's the point of an 80db muffler? That's the same as stock, right? There are a number of reasons why the 80db SPO mufflers are attractive to many of our customers. One reason, of course, is that they look great! The polished stainless steel shell won't rust, and minor scratches can easily be polished out. Another reason is that, in spite of meeting the EPA noise limit of 80db, these mufflers make more power, and sound good to boot.