CamPingSurvivals 26in 150kg 21-Speed Shimano Variable Speed High Carbon Steel Land 09312479Introductions: Here is 26 Inch 21 Speed Three Wheel Foldable Mountain Bike. This bike uses an High carbon steel frame, which is more secure. It also uses a thick shock absorbing front fork, which can comfortably cope with various road sections and has a good shock absorbing effect. The important thing is that this mountain bike is foldable, convenient and easy to store, you can easily carry it in Bus, ground drop, trunk, etc. And it is easy to