This shark fin is bolt on!! Attaches to rear caliper carrier, no welding required. Great disk cover, installs easily. All required hardware supplied. Some of the very early A models (1987/99?) might require tapping of the holes that are alreay there. Hard anodized black, A proven performer, CNC machined in USA by Eagle MFG & Eng! (remember, fits 1987-2007 only)