ARP Perma-Loc Rocker Arm Adjusters Jacket

ARP Perma-Loc rocker arm adjusters are high-performance rocker arm nuts (also called poly locks or rocker arm adjusting nuts). They are built to stay put, so you don't have to keep re-tightening your valvetrain. ARP's patented design addresses a common annoyance in performance engines: adjusters that loosen and need repeated readjustment.

Key Features:

• Premium material: heat-treated, premium-grade 8740 chrome moly steel with 190,000 psi tensile strength.
• Through-hardened body: the adjuster is heat-treated all the way through, not just case hardened. This reduces the thread movement common to other adjusters.
• Precision-machined threads: the threads are machined perpendicular to the base. The adjuster seats evenly and applies pressure around a full 360° circle.
• Flush-ground set screw: the locking set screw is machined flush, not pointed. This gives optimum contact with the rocker arm stud.
• Exclusive 12-point head: the compact head holds your wrench in position while you lock the set screw with an Allen wrench.
• Easy installation: no special tools are required.

The Perma-Loc line is made in the USA by ARP. It gives engine builders and racers a dependable, repeatable valve lash setting. Because rocker arm designs vary between manufacturers, check the thread and physical dimension requirements of your rocker arms and studs against the specific part number.