The main frame is made of aerospace-grade composite carbon fiber, multi-layer composite carbon fiber (T700) technology, lightweight and structural strength reach the first-class level, can withstand extremely high and extremely low temperatures, have high strength, high temperature resistance, corrosion resistance, etc. Features. The backrest can be easily folded forward, and the large wheels can be quickly removed with one button. The whole vehicle is designed for efficiency and speed, and the conversion efficiency is 5%-20% higher than that of other metal frames.