Turbo S-tube muffler, Made from 304 stainless steel for maximum corrosion resistance. This muffler has 2-1/4" ID center inlet and a 2-1/4" OD center outlet with a 2-1/4" core and shell size 5" x 9" x 14" with an overall length of 18" with a mill finish. Stainless Works is the only manufacturer to make the body, core, and packing out of 304 stainless steel. Exclusive louvered core creates a sweet "Street Rod" deep tone that is very aggressive. These are TIG welded for strength and durability. These kits come with a lifetime warranty and proudly made in the USA.