Dragonfly Bulletproof Bullnose 4045 Propellers are specially designed for mini multirotors, like ZMR180. They are composite props with a slight change in mixture, offer extra strength when compared to other propellers. Color: Black / Green (optional)Size: 4*4.5Weight:3.5g/pc ( update the weight on Octorber 13th)Quantity: 4 pcs (4pcs are the same rotation direction, CW/CCW optional)