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 diameter9.5″ / 241mmPropeller pitch6″ / 152mmHubthickness7/16″ / 11.1mmShaft diameter1/4″ – 5/16″ / 6.35mm – 7.94mm *Propeller Weight0.71oz / 20.1gDirection of rotationNormal / TractorMaterialGlass Fiber R CompositeColorBlack