UDI U841 Nano RX4 Quadcopter with Video Camera (Black)The U841 is UDIs most versatile quadcopter to date because it can be built into 4 different configurations. Firstly there is a minimal setup with no accessories, this gives you the optimum flying performance and least weight. Then you can add the guards to that for added protection as you get used to it or for flying indoors. Then there is a car setup, this has 4 wheels and allows you to drive the quadcopter along the floor. Finally, there is big