DO NOT BUY! A second non-functioning D-30 drone was dispatched. The instruction manual is poorly written, the transmitter did not start the motors. The Tomzon-U application hangs on the calibration page. Tech Support Tip: Use the Tomzon U app to launch and fly. China customer support with email replies in 48+ hours. Just cut and paste the answer from the manual. Promises are made, but they are soon ignored. Buyer Warning. If you want to fly it, you have to leave it. The height and duration of the flight depend on the strength of the hands