1. The altitude permit set, including altimeter, programming unit and USB, is a device to limit the altitude and time of motive power. It is also used to install on the model to record the real-time condition, through which you can learn the maximum height, launch altitude, launch time, working temperature etc..

2. The programming unit is used  to read the relevant data and change setstates.

3. USB adapter is used to upload the flying data to PC.