JMT&reg; 10x4.7 3K Carbon Fiber Propeller CW CCW 1047 CF Props Blade For RC Quadcopter Hexacopter Multi Rotor UFO Adopts the high quality 100% 3K all carbon fiber board which imported from Japan improve material. Each pair of propellers has perfect dynamic poise and static balancing which balance by manpower. Especially improves the air-powered efficiency and aerofoil stability very strong and light weight The Bore Dia is 6.3mm,With 4 pcs washer,2 pcs 5mm,2 pcs 6mm Comes with 5mm and 6mm aluminium ring