AV&V Tulip style valves feature the highest flow level on the market. They are one piece forged from a racing grade stainless steel alloy. Each valve has a bearing quality hardened tip at the end of the stem to prevent premature wear with high-lift applications. Valves with the 5/16" (.3106"-.3125") stem valves also features a 45 degree angle below the lock groove to facilitate valve seal installation. AV&V valves are heat treated with a special process and the stem is centerless ground to a micro finish for a longer life.