Chambered round muffler, Made from 304 stainless steel for maximum corrosion resistance. This muffler has 2-1/2" ID center inlet / outlet with a 2-1/2" core and mill finish. Exclusive louvered core creates a sweet "Street Rod" deep tone that is not overly aggressive. On a 1-10, 10 being the loudest, these mufflers are an 8. Mufflers are sized so that they can be reversed for an even more aggressive sound. These are TIG welded for strength and durability. These kits come with a lifetime warranty and proudly made in the USA.