GF Series is specially designed for sport flying and high performance model R/C airplanes with electric motors or glow engines. Made of Glass Fiber Reinforced Composite for strength & durability.Propeller diameter11″ / 279mmPropeller pitch4″ / 102mmHubthickness1/2″ / 12.7mmShaft diameter1/4″ – 5/16″ / 6.35mm – 7.94mm *Propeller Weight0.92oz / 26.1gDirection of rotationNormal / TractorMaterialGlass Fiber R CompositeColorBlack