Automatic Rebound Design Our POYIPI abdomen wheel adopts automatic rebound technology, equipped with a intelligent auxiliary brake system, and a built -in brake device to ensure that the steel rebound is smoother. Ab Roller with Elbow Support The upgraded version of the POYIPI abdominal wheel is equipped with elbow support design to improve the stability during exercise, reduce side shifts, and avoid excessive force of the arm. In this way, you can activate the abdominal muscles more accurately and effectively, focus on training abdominal and core muscles, and do not need to worry about arms fatigue or injury.