The Double Wheel Exerciser Features Two Non-Skid Wheels Welded To A Handle. This Design Grants Extra Safety And Stability, Compared To Balancing On One-Wheel Exercisers. The Anti-Slip Grips Are Made Of High Quality Rubber Which Ensures The Sturdiest Grip During Workout. This Wheel Exerciser Helps You Strengthen Muscle Groups Including Shoulders, Arms, Back, Waistline And Abs.