[Auto Rebound Design]Our 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 system makes the rebound smoother and protects the user from injury. [Multifunctions]Besides traditional exercise, you can also practise plank support to fully exercise your core muscles, including arm, chest, abdomen, back, buttocks and lower body muscles, etc. [Double Wheel Design]Different from single or thin wheel Ab wheels on the market, this elbow support abdominal wheel has 99MM 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. [Wear- material] The roller is wrapped with soft material, which has good sound insulation effect. It is to use and 't hurt the floor. The thickened foam pad design protects the elbows from damaging during long-time exercise. Its sponge grip, which is non-slip, sweat-absorbent, comfortable, fade- and , will not make noise or scratch the floor, and has a longer service life. [Convenient Design]Equipped with a mobile phone holder, stable and not falling off. Fully combine sports with entertainment to make sports more exciting. Colour:light grey Material:PP++steel pipe Package Contents: 1 x Ab Roller Wheel 1 x kneeling pad Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.