Kibblewhite Black Diamond valves are CNC-machined from one-piece forgings of EV8 stainless steel, impregnated by a special German process to a depth of .002 in. with a surface buildup of .0002 in. This proprietary, multi-stage process reduces friction and provides superior resistance to wear and corrosion over traditional chrome and nickel electrolysis plating processes. These valves go through an oxiding and polishing process that creates an extremely smooth surface finish that's easy on valve guides, and there's nothing to flake off and get trapped between the valve and guide to cause seizure or wear! Kibblewhite Black Diamond valves are designed using Finite Element Analysis software, with profiles tested on Kibblewhite's computerized flow bench to provide excellent flow characteristics. These strong, reliable, and lightweight valves are your ticket to ultimate valvetrain performance!