Value-priced BORLA(R) ProXS mufflers share many of the hottest features of our performanceline. Including high-quality 300 Series austenitic stainless steel construction. Sizes are available for import anddomestic cars and trucks. Un-Notched necks are designed for weld in installation. If clamping, use 3 inches wide band clamps 18004. Alternate muffler with Notched necks is 400480. Use 1 inches wide band clamps 18325.