MASTER AIRSCREW ELECTRIC PROP 8 X 4 Electric Only Series is dedicated exclusively to electric motor r/c airplanes and multi rotors. Features wide, thin under-cambered blades for optimum lift, flight duration and power draw. Tractor and pusher props available for twin engine airplanes. Made of Glass Fiber Reinforced Composite. Propeller diameter 8" / 203mm Propeller pitch 4" / 102mm Hub thickness 3/8" / 9.5mm Shaft diameter 1/4" / 6.35mm ** Propeller Weight 0.37oz / 10.5g Direction of rotation Normal / Tractor Material Glass Fiber R Composite Color Black