MASTER AIRSCREW 11 X 7.5 PROP GF SERIESPerformance Propellers for Model Airplanes - GF Series 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 diameter 11" / 279mm Propeller pitch 7.5" / 191mm Hub thickness 1/2" / 12.7mm Shaft diameter 1/4" - 5/16" / 6.35mm - 7.94mm * Propeller Weight 1.06oz / 30.1g Direction of rotation Normal / Tractor Material Glass Fiber R Composite Color Black