BORLA Hanger/ Isolator Kit is designed fo use with custom installations. Kit contains (4) 5/16" diameter and (2) 7/16" diameter stainless steel rods, and (2) high-temperature rubber isolators. Natural mill finish can be brushed or polished prior to installation. To see how to use these hangers check out the "How to Install Video" Link. Hanger/Isolator Kit.