Bridal Mehendi Designs For Full Hands And Legs Borla 1.23 x 8.5 x 5.5 x 4 XR 1 Multi Core Racing Muffler. XR 1 Multi Core Racing Muffler. 4" Center Inlet 4" Center Outlet 6. 25" Round x 23" Long Body 28" Overall Length. Long body design works well on SUV & truck applications but can be used on a wide range of vehicles including rotary engine equipped vehicles. It features BORLA'S patented Multi Core 6 tube design for maximum flow, horsepower, and torque. The Multi Core portion of XR 1 mufflers flows better than straight tubing. Recommend for high horsepower applications. Reversible design for installation flexibility. T 304 Stainless steel will never rust. Natural mill finish can be brushed or polished prior to installation. 100% welded construction for strength. High temperature T 304 stainless steel wool packing for sound control. Best of all, it's made in the USA. Just what you'd expect from the world's most experienced (and most winning) exhaust brand. 4" Center Inlet 4" Center Outlet 5. 5" x 8. 5" Oval x 23" Long Body 28" Overall Length Can be used on a wide range of vehicles including rotary engine equipped vehicles Multi Core 6 tube internal design. High temperature SS wool for sound control Long body design works well on SUV & truck applications Universal muffler. Reversible design.