This kit repairs 2 damaged suspension rails. Egg shaped holes are easily repaired without removing suspension or components providing a cost competitive alternative to replacing the entire rail. Can be used on new rails to prevent future damage. Grade 8 replacement axle bolt and mounting hardware all have pre-applied Vibra-Tite thread locker. Automotive style locknuts, and lock washers are provided to prevent future looseningAdd to new rails to prevent future problems!.