3/8" Polylock Rocker Arm Nut Set (Suits: Aluminum Rockers) The Speedmaster design incorporates open-fin

The Speedmaster design incorporates open-fin spacing that promotes airflow through the radiator to enhance the cooling and help eliminate clogging

They feature larger radius stud fillets for extra strength

These water pump pulleys are made from a 356 aluminum alloy that is heat-treated to T-6 specs

improved meshing to reduce tooth jump

plus a reserve

3/8" Polylock Rocker Arm Nut Set (Suits: Aluminum Rockers) The Speedmaster design incorporates open-finSpeedmaster rocker arm adjusting nuts are high quality polylocks designed for full roller rocker arms. Made from heat treated, premium grade 4140 chromoly steel, these adjusters provide 190,000 psi tensile strength for the utmost in reliability. Precision CNC machined threads to ensure optimum seat pressure, flush machined set screws for proper contact on the studs, and, best of all, they don't require any special tools for installation. They're