If you have ever installed a rocker stud into a cylinder head and watched it wobble as it screwed in  you knew from the beginning that the rocker geometry was going to be inconsistent all over the place. ARP rocker studs are concentric within.005 T.I.R. thread pitch to thread pitch. They run-in straight and true. Lengths are exact  designed to provide positive seating every time. An extra-large radius base offers greater resistance to flex. Available in both High Performance and Pro Series models. 
 NOTE: Not to be used with OEM-style, self-locking nuts. To be used with ARPs patented Perma-Loc adjusters
 HIGH PERFORMANCE SERIES
Made of 8740 chrome moly forgings and heat-treated to 180,000 psi. Excellent for E.T. Bracket Racing, limited rule oval track
competition and street use. Tip ground flush for optimum adjuster seating. 
 PRO SERIES
Designed for competition applications, ARPs Pro Series rocker arm studs are made of premium grade 8740 chrome moly steel and heat-treated to a tensile strength of 200,000 psi.
 IMPORTANT TECH NOTE
It is highly advisable to determine what the optimum rocker arm stud length is for your particular application. This is especially true when long pushrods and valves are employed  you should raise the installed height of the rocker arm to compensate for the longer-than-stock components.
Application:
- UNKNOWN NO FITMENT SPECIFIED