1.[HIGH LOAD BEARING CAPACITY - 440LBS]Constructed with high-quality steel tube. The strength training pull-up bars used special structure. The greater the pulling force to the pullup bar, the r and firmer the two ends of the base against the wall. It ensures maximum stability and training without wobbling or slipping, which can hold up to 440Ibs. 2.[ADJUSTABLE PULL UP BARS]Door frame pull up bar adjustable length for easy fitting in most of door frame between 27.6'- 36.2'(70cm-92cm). It can be installed in any gement walls, security doors, solid wood doors, corridors but not including fragile door frames, glass doorframe, hollowed doorframe, ceramic tile wall, Fragile Wall. Suitable for standard doorway, perfect for home, garage or office use. 3.[NO INSTALLATION REQUIRED & AUTOMATIC LOCKING]Our products do not need to be installed, they can be used after being disassembled, and are equipped with instructions. Using the anti-reverse rotation design locking structure is twice as as the buckle type. Upgrade with a large size PVC pad and texture design. 4.[NO SCREWS & NO DRILLING]No screw, no drilling, perfectly protect your door frame and wall. Upper body workout bar is equipped with level meter, through the middle position of the bubble to judge that the pull up bar is in a level state or not. (Note: The correct installation method is that the arrow of the lever points upwards and the horizontal liquid bubble is balanced).