Ferrea Competition Plus valves are renowned as the most reliable extreme valve in the industry. We use special quality alloys for the aerospace industry to manufacture the valves, including EV8-Z18, which provides high tensile strength. The exclusive, two-stage, slow forging process ensures proper flow and virtually eliminates any damage to the material structure. The valves are then heat treated and stress relieved within 48 hours, which is a key foundation for our molecular integrity. Fits: AUDI 2.0T FSI - DOHC 16 VALVE - 2006-2008 Dimensions: Head diameter: 28mm Shaft diameter: 5.97 mm Overall length: 102 mm Tip length: 5 mm Ferrea Competition Plus valves are known as the most reliable extreme valve in the industry.For the production of valves we use special quality standards for the aerospace industry, including EV8-Z18, which provides high tensile strength. An exclusive two-stage, slow forging process ensures proper flow and virtually eliminates any damage to the material structure. The valves are then heat treated and tempered within 48 hours, which is the key foundation of our molecular integrity. Fits: AUDI 2.0T FSI - DOHC 16 VALVE - 2006-2008Dimensions: Head diameter: 28mmStem diameter: 5.97 mmOverall length: 102 mmTip length: 5 mm