Create your own custom systems using Borla(r) Hot Rod Kits. All components in this kit are T-304 stainless steel which will never rust. Elbows and u-bends are mandrel bent for maximum flow. Kit contains (4) 45 degree elbows (4) 90 degree elbows (4) 180 degree u-bends and (2) 5' long straight tubing sections. Brushed finish for sharp appearance it can be polished to a mirror finish prior to installation. Size is outside diameter.