MASTER AIRSCREW 6 X 3.5 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 6" / 152mm Propeller pitch 3.5" / 89mm Hub thickness 5/16" / 7.9mm Shaft diameter 1/8" - 3/16" / 3.18mm - 4.76mm * Propeller Weight 0.24oz / 6.8g Direction of rotation Normal / Tractor Material Glass Fiber R Composite Color Black