Skunk2 Alpha Series Valves for the Honda K20 and K24 are manufactured from HNV - 3 martensitic steel (IN) and EV8 austenitic steel (EX) one - piece forgings. Each valve is heat - treated using a proprietary process for extraordinary strength and durability and then hard chrome plated to further increase strength, significantly reduce friction, and increase corrosion resistance. Other valves may appear similar, but only Alpha Series Valves feature specially designed valve head profiles to optimize airflow. Skunk2 designs, develops, and tests its entire valvetrain lineup in - house to ensure superior quality and maximum performance gains. Skunk2 valvetrain components provide exceptional performance, reliability, and quality and are standard - issue on each Skunk2 vehicle that we build and support.