Chevy 12 Bolt Full Spider Rock Guard, Maybe Full Spider is an understatement, designed for PCP Polished Aluminum Differential Covers for the rear axle for full protection for the rear of your big Chevy. There is not a rock guard or cover on the market that offers more protection than the PCP Full Spider does. The PCP Spider® Rock Guard is second to none, designed with not only protection in mind but also looks. The 12 Bolt Spider includes a .375 thick CNC plasma cut flange, .625 Rd. Cold Rolled Steel legs, Fixtured Mig welded welds, CNC machined counter bored bolt holes, Normalized and shotblasted, Phosphate primed and Powder Coated a durable black hammertone. For more color choices click on the "Powder Coating Options" button below. All stainless steel mounting bolts are included. Cover not included.