To further improve the safety for everyone to use at ease, make a height adjustment function easy and flexible and remarkably reduce the manufacturing cost of an appliance.

The main material of the appliance is changed to a light steel pipe. In its design a safety outer frame (1) and tower outer pipes, right and left (3) are provided to be connected with tower inner pipes, right and left (2) at the top and the bottom, thereby improving the safety during the exercise. A pipe with a small diameter is used for a knee laying pipe (7), and fitting pipes in each other and inserting height adjustment bolts (9) into height adjustment bolt holes (8) serve a height adjustment function.