This is the last step in the construction of the Gyro Chaser model rocket. It shows how to install the rubber bands onto the rocket, which deploy the blades when they are kicked out of the model rocket at apogee. You'll also balance the rotor hub so that the rocket doesn't wobble as it descends. There is an optional step of installing a launch lug. If you are using a launch tower, like the one from Apogee Components (http://www.ApogeeRockets.com), then you do not need to install the launch lug.