Vforce4X Replacement Reed Petal 4Px412CdV Force 4 Reed Valve SetLong reed stops added to progressively slow reed petal tip velocity for increased petal durability Reduced frontal area of the central wing combined with a more aerodynamic shape Airfoil shape added to cage tip to increase velocity from outer ports Combined reed tip area is increased by 10. 5% for better airflow Advanced reed petal resin system, carbon fiber and lay up Pre curved reed petal ensures better seal at the tip Wider