This upgraded QAV250 Plus "Unibody" frame plate in 3mm carbon fiber material enables you to extend the QAV250 up to a 300 size allowing 6" propellers.
The new carbon fiber unibody is designed to give it maximum strength. The arms now have more carbon and smaller holes giving them extra strength. Also the point where the arm meets the body has been significantly beefed up. This new design can handle the harsh impacts a high speed racing frame takes.