These are directly compatible with our custom ARP turbo stud kit, found HERE. Stage 8 Locking Turbo Kits easy to use and they are real assurance against horsepower loss or gasket failure created by loose nuts or bolts. The unique patented and trademarked functional design is just three pieces: a bolt (4130 Alloy Steel), a locking retainer and a spring clip or, depending on the application, a nut, a locking retainer and a spring clip.  The turbo bolt kits are application specific as either metric hex head 6 point or metric nut. All Stage 8 Locking Turbo Kits are sold with all of the necessary hardware for your application.