Features: METER IS NOT INCLUDED Auto Rebound DesignOur ab roller adopts automatic rebound technology, which helps protect muscles from stress during exercise. Moreover, the auto-rebound feature helps beginners tighten their core, standardize movement, and keep exercising for longer periods of time. The built-in smart braking system makes the rebound smoother and protects the user from injury. Multi functionsBesides traditional exercise, you can also practice plank support to fully exercise your core muscles, including arm, chest, abdomen, back, buttocks and lower body muscles, etc. Double Wheel DesignDifferent from single or thin wheel Ab wheels on the market, this elbow support abdominal wheel has 105MM wide front and rear wheels for smooth rolling and better control. It can help you exercise every muscle and core while controlling your body more safely, especially for beginners.Convenient DesignEquipped with a mobile phone holder, stable and not falling off. Fully combine sports with entertainment to make sports more exciting.