The K-DF-MINIHELI-ROTOR-2 is a set of two main rotors for your micro RC helis.
These rotors are able to fit any palm size mini two channel RC helicopter, just remove the broken rotors and then press the new ones on to the main shaft. Be careful while doing this, if you push or pull them too hard, you can damage your helicopter and break the rotors.
Each rotor is equipped with a pair of small weights on the bottom of the top section. These weights help stabilize the helicopter, so you will need to replace the main rotors if they are missing.
Use this set of main rotors to replace the rotors on your micro RC helicopters if they break. It is a good idea to buy the replacement rotor set ahead of time, so that you have them when you need them.