Wiseco Professional Series pistons are designed to take the hard-driving abuse from your performance engine. They're forged from either 2168 or 4032 aluminum alloy for maximum strength, and then precision CNC-machined to their intricate final configurations under close tolerances. Where applicable, designs incorporate strength provisions to deal with turbocharging, supercharging, and nitrous. Chromoly wrist pins and Spirolox retainers are included.