Item Type: Automatic Rebound Abdominal WheelMaterial: PP, metalBattery: Timer: 1 x 120mAh LR1130 button cell (built in)1,AUTOMATIC REBOUND: Abdominal roller wheel features an automatic rebound design and braking system that uses steel springs to provide a effortless roll.2,ELBOW SUPPORT: Elbow support pads on this abdominal roller wheel provide extra cushioning and support, making it comfortable to use, which help reduce the injury during workout.3,DOUBLE WHEEL DESIGN: Abdominal roller wheel has a wider double wheel design that provides a stable and smoother roll, allowing you to target different parts of your abdominal muscles with precision.4,TIMER FUNCTION: Abdominal roller wheel comes with a built in timer that allows you to track your workout time, making it easy to stay on track and monitor your progress.5,SLIP RESISTANT: 5 layer slip resistant material, anti slip layer, reinforcement layer, shock absorption layer, noise reduction layer, support layer, which provides a quiet training environment.1 x Abdominal Wheel1 x Timer1 x Support Frame1 x Kneeling Pad2 x Elbow Support Pad2 x Grip Support Tube1 x Instruction Manual