When you exercise your arms, , you need to connect the ends of the tube to the door handle, then you can attach the center to the door buckle and fasten it to the door, stretch using the handle on the other side. When you exercise your legs, replace the handles with ankle bucklesm, and it's very easy to install, you can exercise anywhere with a door. Applicable to the crowd:fitness exerciser, slimming Lady, office people, students and housewife.