Efly Smart X Remote Control Quadcopter Drone RTF, Smallest RC Toy Helicopters 4 Channel for Sale (Green) The smallest rc quadcopter: size - 40*40*22 mm. Lightweight airframe with nice durability; USB charging cable allows to charge by computer. The latest 4 Channel with six axis gyroscope sensitivity that permits super stable flight. Three speed modes - low & middel & high,easy to control; Two Fly Mode:Indoor/Outdoor. Three speed modes - low & middel & high,easy to control; Two Fly Mode:Indoor/Outdoor.