Jmt 4 Pairs 10x4.5 3k Carbon Fiber Propeller Cw CCW 1045 Props Cons for DJI Quadcopter Hexacopter UFO Just fit for DJI Motor,DJI Model 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 8mm,No washer request.